Histamines that do not cause headaches. Generations of antihistamines

Question: Can antiallergic antihistamines harm a person if taken on a regular basis?

Answer: It is better to pass tests for allergens on the machine "IMEDIS Expert", and further exclude contacts with identified bioresonance test allergens. Also, if possible, it is treated by a bioresonance therapist and for many years to take homeopathic and bioresonance preparations prescribed during the treatment of bioresonance therapy, as well as during exacerbations or during the allergic season, take new-generation antihistamine drugs selected by a bioresonance test or pendulum.

You need to drink new generation antihistamines 1 time per day until the allergy symptoms disappear. If contact with the allergen cannot be avoided, then you will have to take an antihistamine (anti-allergic drug) daily, there is nowhere to go from this, alas. When exposed to an allergen without an antiallergic drug, a severe allergic reaction can develop, which in turn can lead to death, coma, and allergies can also turn into asthma.

There are people who sit on new generations of antihistamines during their lifetime and nothing.

Of course, pills are no sweetie, and antihistamines are no exception. In a state of reaction, do not try to do without them. Allergens will need to be removed from the field of the body on time, and then it may be too late.

Antihistamines

Antihistamines are a group of drugs whose principle of action is based on the fact that they block H1 and H2-histamine receptors. This blocking helps to reduce the reaction of the human body with a special mediator histamine. What are these medicines for? Doctors prescribe them during allergic reactions. Possessing good antipruritic, antispastic, antiserotonin and local anesthetic effects, antihistamines perfectly help with allergies, and also effectively prevent bronchospasm caused by histamine.

In accordance with the time of invention and release on sale, the whole variety of allergy remedies is classified into several levels. Antihistamines are classified into first, second, third and fourth generation drugs. The medicines included in each generation have their own specific features and properties. Their classification is based on the duration of the antihistamine effect, the existing contraindications and side effects. The medicine necessary for treatment must be selected based on the characteristics of each specific case of the disease.

Generations of antihistamines

First generation antihistamines

Preparations of the 1st (first) generation include sedatives. They work at the level of H-1 receptors. The duration of their action is four to five hours, after this period it will be necessary to take a new dose of the drug, and the dose should be large enough. Sedative antihistamines, despite their strong effect, have a number of disadvantages. For example, they can provoke dry mouth, dilated pupils, blurred vision.

Drowsiness and a decrease in tone may occur, which means the impossibility of taking these drugs while driving a car and other activities that require a high concentration of attention. They also enhance the effect of taking other sedatives, sleeping pills and pain medications. The effect on the body of alcohol mixed with sedatives is also enhanced. Most first generation antihistamines are interchangeable.

Their use is advisable in case of allergic problems with the respiratory system, for example, when coughing or nasal congestion. It is worth paying attention to the fact that first-generation antihistamines fight cough well. This makes it appropriate to use them in bronchitis.

They will also be useful for those people who suffer from chronic diseases associated with difficulty breathing. Their use is quite effective in bronchial asthma. They can also have a fairly good effect in the treatment of acute allergic reactions. So, for example, their use will be appropriate for urticaria. The most common among them are:

suprastin

diphenhydramine

diazolin

tavegil

Also often on sale you can find peritol, pipolfen and fenkarol.

Second generation antihistamines

Preparations of the 2nd (second) generation are called non-sedative. They do not have such a large list of side effects as the drugs that make up the first generation of antihistamines. These are drugs that do not cause drowsiness and do not reduce brain activity, and also do not have cholinergic effects. A good effect is given by their use in itchy skin and allergic rashes.

However, their significant drawback is the cardiotoxic effect that these drugs can cause. Therefore, non-sedative drugs are prescribed only on an outpatient basis. In no case should they be taken by people suffering from diseases of the cardiovascular system. Names of the most common non-sedative drugs:

trexil

histalong

zodak

semprex

fenistil

claritin

Third generation antihistamines

Antihistamines of the 3rd (third) generation are also otherwise called active metabolites. They have strong antihistamine properties and have virtually no contraindications. The standard set of these drugs includes:

cetrin

zyrtec

telfast

These drugs do not have a cardiotoxic effect, unlike second-generation drugs. Their use gives a positive effect in asthma and acute allergic reactions. They are also effective in the treatment of dermatological diseases. Quite often, third-generation antihistamines are prescribed by doctors for psoriasis.

New generation drugs are the most effective and harmless antihistamines. They are non-addictive, safe for the cardiovascular system, and also have a long period of action. They belong to the fourth generation of antihistamines.

Fourth generation antihistamines

Preparations of the 4th (fourth) generation have a small list of contraindications, which are mainly pregnancy and childhood, but, nevertheless, it is worth reading the instructions and consulting with a specialist before starting treatment. The list of these drugs includes:

levocetirizine

desloratadine

fexofenadine

Based on them, a larger number of drugs are produced, which, if necessary, can be purchased at a pharmacy. These include erius, xizal, lordestin, and telfast.

Forms of release of antihistamines

There are several forms of release of drugs that block histamine receptors. In most cases, their most convenient type to use are tablets and capsules. However, on the shelves of pharmacies you can also find antihistamines in ampoules, suppositories, drops and even syrups. The action of each of them is unique, so only a doctor can help you choose the most appropriate form of taking the medicine.

Treatment of children with antihistamines

As you know, children are more prone to allergic diseases than adults. A qualified allergist should select and prescribe drugs for children. Many of them in the list of their contraindications are of children's age, therefore, if necessary, from the application to the preparation of a course of treatment, it is necessary to be especially careful. Children's organisms can react quite sharply to the effects of the drug, so the well-being of the child during the period of their use must be monitored very carefully. In case of side effects, the drug should be stopped immediately and consult a doctor.

For the treatment of children, both somewhat outdated medicines and more modern ones are suitable. The drugs that make up the first generation are mainly used to urgently relieve acute allergy symptoms. During long-term use, more modern means are usually used.

Antihistamines are not usually available in special "children's" forms. For the treatment of children, the same drugs are used as for adults, but in smaller doses. Drugs such as zyrtec and ketotifen are usually prescribed from the moment the child reaches the age of six months, all others - from two years. Do not forget that taking medicines by a child should be under the supervision of an adult.

In the case of an illness of a small child, the selection of antihistamines is much more complicated. For newborns, medications that have a slight sedative effect, that is, first-generation drugs, may be suitable. The most commonly used in the treatment of very young children is suprastin. It is safe for both babies and older children, as well as for nursing mothers and pregnant women. Depending on the disease and the condition of the child's body, the doctor may prescribe him tavegil or Phencarol, and in the case of an allergic skin reaction, an antihistamine cream. For infants, the same drugs are suitable as for newborns.

Antihistamines during pregnancy and lactation

Due to the increased production of cortisol in a woman's body, allergies during the childbearing period are quite rare, but, nevertheless, some women still face this problem. During pregnancy, the intake of absolutely all medications must be agreed with the doctor. This also applies to allergy remedies, which have a fairly wide range of side effects and can harm the child. The use of antihistamines is strictly prohibited in the first trimester of pregnancy; in the second and third trimesters, they can be used, observing, however, the necessary precautions.

Unintentional ingestion of the drug into the child's body is possible not only during pregnancy, but also during breastfeeding. During lactation, the use of antihistamines is highly undesirable and is prescribed only in the most urgent cases. The question of which remedy a nursing woman will use can only be decided by a doctor. Even the newest and most modern medicines can cause irreparable harm, so in any case, do not self-medicate by feeding your baby with your milk.

Side effects of antihistamines

As mentioned earlier, the body of each person is individual, and only a specialist can choose the right remedy for treatment. Taking the wrong medicine for a person and violating the dosage can seriously harm health. The harm of antihistamines can manifest itself in addition to their usual side effects such as drowsiness, runny nose and cough in violation of the timing of ovulation in women, the occurrence of allergic edema and asthma. Therefore, be sure to consult your doctor before you start drinking the medicine, and strictly follow the recommendations for taking it.

Drug treatment of allergies, antihistamines

How antihistamines work

Antihistamines of the "old" and "new" generations

What is the difference between 1st, 2nd and 3rd generation antihistamines

Fundamentals of drug therapy

There is such a substance - histamine. It is released during an allergic reaction and is responsible for the development of bad symptoms, from skin manifestations to very severe life-threatening reactions, such as anaphylactic shock. That's why antiallergic drugs are called ANTIhistamines.

They block histamine receptors and thus stop the development of allergy symptoms.

Depending on the type of reaction, antihistamines are prescribed by injection (for severe forms) and orally (for milder ones). It is understandable: if we inject the drug with the help of an intramuscular or intravenous injection, it instantly enters the bloodstream and is included in the work. And if we drink this medicine, time must pass before the active substance is absorbed into the blood from the gastrointestinal tract.

All anti-allergy drugs can be divided into several groups:

1. Symptomatic drugs.

2. Medicines for the treatment of chronic allergic inflammation in the affected organ.

3. Medicines for local therapy.

Symptomatic drugs are intended to alleviate the course of allergic diseases. The leading place among them belongs to drugs called antihistamines.

These agents counteract the damaging effects of the main mediator of allergic reactions, histamine. Today, doctors are armed with three generations of antihistamines that differ in their characteristics.

The selection of antihistamines is carried out individually, taking into account the nature of food allergies, the age of the child and the nature of concomitant diseases. Symptomatic drugs also, for example, include bronchodilators. They are used for asthma attacks.

Antihistamines for the treatment of chronic allergic inflammation in the affected organ are divided into non-hormonal and hormonal. The latter drugs are more powerful and effective.

The appointment of drugs in this group is carried out depending on the clinical manifestations of food allergies, the severity of the disease, the age of the child. It must be remembered that these drugs are generally effective only with long-term regular use.

We must remember that drug therapy for food allergies is a long process, you need to patiently and persistently follow medical recommendations.

We must also remember that some treatments for food allergies are absolutely contraindicated and can harm the child. So, with food allergies, treatment with herbs and many traditional medicine is contraindicated, and psychotherapy and reflexology, except for bioresonance treatment, almost do not give a significant effect.

Treatment with herbs and preparations based on them increases the risk of developing an allergy to plant pollen in the future. The same "service" can be provided by biologically active additives, which often contain plant components.

Antihistamines are standard therapy for atopic dermatitis. They are used as an additional remedy for external treatment with severe itching and associated rashes.

Antihistamines are divided into three generations:

means of the 1st "old" generation;

means of the 2nd and 3rd generations ("new" generation).

Antihistamine drugs of the 1st "old" generation

Antihistamines of the 1st generation are more often used to treat acute reactions, in the treatment of itchy allergic dermatoses. Most of them are available in solutions in ampoules, but there are forms in tablets, syrups and powders.

Antihistamines of the 1st "old" generation (forms for oral administration)

Chloropyramine, Clemastine, Dimetindene, Quifenadine, Hifenadine, Mebhydrolin, Ketotifen.

Disadvantages of older generation antihistamines:

Incomplete connection with H1 receptors, as a result of which relatively high doses are required;

Short-term action - taking several times a day

Development of addiction - it is necessary to alternate drugs of different groups every 10-14 days

Sedative and hypnotic effect

Antihistamine drugs of the 2nd and 3rd "new" generations

Loratodin, cyterizine, fexofenadine, desloratadine.

Currently, in the treatment of atopic dermatitis, antihistamine drugs of the "new", that is, the 2nd and 3rd generations, are widely used.

Antihistamine drugs of the 2nd and 3rd generations are used for basic and anti-relapse therapy.

Antihistamines of the "new" generation do not have sedative and hypnotic effects. They have a selective effect, causing blockade of only H1-histamine receptors. The duration of their action is up to 24 hours, so most of these drugs are prescribed once a day.

After taking most antihistamines, their residual effect may last for one week after withdrawal (this circumstance must be taken into account when conducting an allergy examination). A significant difference between the antihistamine drugs of the "new" generation is that they have not only H1-blocking action, but also anti-allergic and anti-inflammatory effects.

If long-term use is necessary, only antihistamines of the “new” generation are used.

The absence of undesirable side effects characteristic of the first antihistamines allows to significantly expand the list of indications for the appointment of modern H1-antagonists.

Benefits of 2nd generation antihistamines over 1st generation:

Rapid onset of action (from 30 minutes - acute cases);

The possibility of taking at any time of the day (including in the first half of the day) good absorption from the digestive tract the possibility of using in young children a long duration of the antihistamine effect (up to 24 hours), which allows you to take the drug once a day.

No blockade of other types of receptors

Lack of penetration through the blood-brain barrier at therapeutic doses

Lack of connection with food intake

Non-addictive, even with long-term use (3 to 6 months)

The almost complete absence of side effects associated with exposure to the nervous and cardiovascular systems.

The use of antihistamine drugs in the treatment of children with atopic dermatitis.

Children after a year, as a rule, are prescribed drugs of a new generation.

The drugs of the "new" generation, which are approved for use in children from 6 months old, are antihistamine drugs based on cetirizine (generic active ingredient).

VACCINATION

Since allergy is an immune disorder, allergic rhinitis and bronchial asthma can be treated with vaccines from allergens to which the child is hypersensitive. Indications for vaccination are determined based on the results of skin tests with allergens.

The vaccine is administered under a special scheme subcutaneously or buried under the tongue. Such treatment is applicable only in children over 5 years of age and should be carried out by an allergist.

And finally, the most interesting question: do allergy medications cause allergies? Yes! We will not go into the technical details of the complex mechanisms that may lead to this development.

Let's just say that an allergy to antihistamines is extremely rare, but it happens. There is only one way out - to change the drug.

Antihistamines are a group of drugs that perform a competitive blockade of histamine receptors in the body, which leads to inhibition of the effects mediated by it.

Histamine is a neurotransmitter that can affect the respiratory tract (causing swelling of the nasal mucosa, bronchospasm), skin (itching, blistering hyperemic reaction), gastrointestinal tract (intestinal colic, stimulation of gastric secretion), cardiovascular system (expansion of capillary vessels, increased vascular permeability, hypotension, cardiac arrhythmias), smooth muscles.

Strengthening its influence cause allergic reactions, so antihistamines are used to combat the manifestations of allergies. Another area of ​​their application is symptomatic therapy / elimination of symptoms in colds.

Currently, there are three groups of drugs (according to the receptors they block):

H1 blockers - used in the treatment of allergic diseases.

H2-blockers - used in the treatment of diseases of the stomach (help reduce gastric secretion).

H3 blockers are used in the treatment of neurological diseases.

Among them, cetrin (cetirizine), phencarol (chifenadine), diphenhydramine, clemastine, suprastin stop the emission (for example, cromoglycic acid) or the action (like diphenhydramine) of histamines.

Available in the form of tablets, nasal spray, drops, including eye drops, solution in ampoules for intramuscular injection (usually for emergency therapy).

There are several generations of antihistamines. With each generation, the number and strength of side effects and the likelihood of addiction decrease, the duration of action increases.

First generation

Before buying a medicine - paracetamol, ibuprofen, antiallergic (antihistamine) drugs, cold and cold remedies, you need to know:

Paracetamol

Pain reliever, antipyretic, anti-inflammatory agent. The active substance is paraacetaminophen, on the basis of which many other similar drugs are produced in different countries, such as acetaminophen, panadol, efferalgan, myalgin, paramol, pilaren, etc.

Benefit. In its action, paracetamol is in many ways close to aspirin, but has less pronounced side effects. It does not reduce blood viscosity, so it is safe to use in preparation for and after surgery.

It is less likely than aspirin to cause allergic reactions and is less irritating to the stomach. Paracetamol is part of many combined preparations in combination with aspirin, analgin, caffeine, etc. It is available in the form of tablets, capsules, mixtures, syrup, "effervescent" powders (panadol, panadon).

Possible harm. When combined with alcohol, it can damage and even destroy the liver. Therefore, it, like aspirin, is dangerous for people who regularly drink alcohol. Paracetamol has a negative effect on the liver and in case of violation of the norm of its intake (in case of overdose).

Exit. Take no more than 2 g per day (4 tablets of 500 mg) - People who drink alcohol daily should stop taking paracetamol.

Ibuprofen

It has an analgesic and anti-inflammatory effect. Ibuprofen is the active ingredient in drugs such as Brufen, Arthryl, Advil, Naproxen, etc. These drugs are chemically identical, but differ in the duration of the therapeutic effect.

Benefit. Help with fever, muscle and joint pain (rheumatoid arthritis, arthrosis, etc.)

Possible harm. If the body is severely dehydrated as a result of heavy physical work, heat, or taking diuretics (diuretics), then ibuprofen may adversely affect the kidneys. The risk of kidney damage increases with regular use of ibuprofen.

Long-term use of ibuprofen is dangerous for the stomach. In people who constantly drink alcohol, taking ibuprofen can affect the liver.

Exit. Try to avoid dehydration. When taking ibuprofen, it is necessary to monitor the work of the kidneys. In no case should you exceed the allowable daily intake (6 tablets of ibuprofen 200 mg or 2 tablets of naproxen 220 mg).

Antiallergic (antihistamine) drugs

The drugs in this group are intended for people suffering from pollinosis (hay fever), asthma, hives or other allergic diseases.

Benefit. They relieve runny nose, sneezing, sore throat, coughing and suffocation, unbearable itching and other symptoms of these diseases.

Possible harm. Most common drugs in this group, such as suprastin, tavegil, diphenhydramine, zaditen, peritol, etc., have a sedative effect, that is, they cause drowsiness, inhibition of reactions, and general weakness. Therefore, it is dangerous to take them for car drivers, pilots, operators, dispatchers, etc., that is, people who require constant attention and quick reaction in difficult situations.

Exit. To avoid the risk, you should take a new generation of antihistamines that do not cause drowsiness and inhibition of reactions, such as claritin, kestin, which act for 12-24 hours. Sedative antihistamines are best taken in the afternoon and at night.

Remedies for the common cold

The action of drugs such as sanorin, naphthyzin, galazolin, otrivin, etc., is that they narrow the blood vessels in the swollen mucous membrane of the nasal passages, as a result of which the nasal passages themselves expand.

Benefit. With a cold, the runny nose is weakened or stops, breathing through the nose is restored, and the headache disappears.

Possible harm. When taking these drugs, blood vessels are narrowed not only in the nose, as a result of which blood pressure may increase in patients with hypertension.

This is especially dangerous for hypertensive patients, since the drugs they take to lower blood pressure will be ineffective. In addition, drugs in this group are dangerous for those who take antidepressants such as pyrazidol, pirlindol, nialamide.

Exit. For people suffering from hypertension, common cold remedies can only be taken under the control of blood pressure. In the event of an increase in pressure, the dosage of antihypertensive drugs should be increased.

Patients with depression who take the listed antidepressants or the like, drugs in this group are contraindicated.

Complex preparations for colds used with antihistamines

Among the complex anti-cold drugs, such as askofen, citramon, sedalgin, alkaseltzer plus, bicarmint, etc. are especially known.

Benefit. They help to get rid of various symptoms of the disease at the same time: cough, runny nose, pain, fever, allergic manifestations.

Possible harm. When taking complex drugs, the so-called "unforeseen overdose" is quite often allowed.

This happens when, with a severe cold or headache, in order to increase the effectiveness of treatment, a complex cold preparation containing aspirin is added to the intake of aspirin. As a result, peptic ulcer disease may worsen or even gastric bleeding occurs.

If, with an allergic rhinitis, in addition to suprastin, you also take a complex preparation containing an antihistamine, then everything together will act as a strong sleeping pill. Sometimes liver disorders are associated with a similar overdose of paracetamol or ibuprofen.

Exit. Before taking a complex preparation for a cold, you should carefully read its composition indicated on the package or in the insert, and do not take separately those medicines that are included in it.

Antiallergic drugs for children: characteristics, principle of action, benefits and harms

Diazolin (mebhydrolin);

Peritol (cyproheptadine).

In principle, the effectiveness of the above drugs has been confirmed by many years of experience, but this same experience indicates a whole bunch of side effects:

All these drugs to a greater or lesser extent affect the central nervous system, providing sedative and hypnotic effects.

Classical antihistamines dry out the mucous membranes. Dry mouth, sputum viscosity in the lungs (which is especially dangerous in acute respiratory viral infections, as it seriously increases the risk of developing pneumonia) - does not have the best effect on the child's condition.

The simultaneous use of first-generation antiallergic drugs with other drugs enhances the effect of the use of the latter. Thus, antipyretic, analgesic, hypnotic effects are enhanced. Especially dangerous is the combination of antihistamines with other drugs that actively affect the functioning of the central nervous system. In this case, the development of side effects up to fainting is possible. The combination with alcoholic beverages is highly undesirable.

The action of such drugs, although effective, is limited to 2-3 hours (some last up to 6 hours).

Of course, it does not come without advantages. Firstly, first-generation antihistamines are relatively affordable, and secondly, they are great for short-term treatment of allergies. That is, if, for example, a child ate an excessive amount of chocolate and a short-term intake of an antihistamine is required, you can safely use the same Tavegil or Fenkarol.

Most first-generation allergy remedies are forbidden to be taken orally by nursing mothers; only their local forms can be used - ointment, cream, spray. The exception is Suprastin and Fenkarol (from three months of pregnancy). Each drug has its own characteristic feature, which is important to consider when drawing up a treatment regimen. So, it is not advisable for a baby prone to constipation to use Tavegil; a child suffering from gastrointestinal diseases is prohibited from taking Suprastin; and children with impaired liver function need to be careful with the use of Phencarol.

For babies under one year old, taking first-generation antiallergic drugs is undesirable. For the smallest, there are more modern drugs that are practically safe and very effective.

The principles of action of antihistamines, the second generation on the children's body

The undoubted advantage of antiallergic drugs of the second and third generation is the absence or minimization of the sedative, hypnotic, CNS inhibitory effect.

In addition, they have a number of other advantages: they do not penetrate the fetoplacental barrier (that is, such drugs can be used during pregnancy);

do not dry mucous membranes;

do not affect the mental and physical activity of the child;

have a quick and long-lasting (up to 24 hours) therapeutic effect - one tablet is enough to forget about allergy symptoms for the whole day;

in addition to antiallergic, they have antiemetic, antiulcer and other actions (some drugs); do not reduce their effectiveness with long-term use.

Perhaps the only drawback of second-generation antiallergic drugs is their ability to have a negative effect on the children's cardiovascular system. Due to the possible cardiotoxic effect, the use of such drugs is not recommended for children with various pathologies of the heart and blood vessels.

Among the most prominent representatives of the second generation:

Claritin (loratidin);

Allergy treatment, antihistamines

Diazolin dragee 50mg №20

Diazolin tab. 100mg #10

Suprastin (chloropyramine) is one of the most widely used sedative antihistamines. It has significant antihistamine activity, peripheral anticholinergic and moderate antispasmodic action.

Effective in most cases for the treatment of seasonal and year-round allergic rhinoconjunctivitis, angioedema, urticaria, atopic dermatitis, eczema, itching of various etiologies; in parenteral form - for the treatment of acute allergic conditions requiring emergency care. It does not accumulate in the blood serum, so it does not cause an overdose with prolonged use. The effect comes on quickly, but is short-lived; to increase its duration, it is combined with non-sedating H1-blockers.

Suprastin injection 2% 1ml amp. No. 5 (Egis, Hungary)

Suprastin tab. 25mg №20 (Egis, Hungary)

Chloropyramine g / x tab. 25mg #40

Tavegil (clemastine) is a highly effective antihistamine drug similar in action to diphenhydramine. It has a high anticholinergic activity, but penetrates the blood-brain barrier to a lesser extent.

In an injectable form, which can be used as an additional remedy for anaphylactic shock and angioedema, for the prevention and treatment of allergic and pseudo-allergic reactions. However, there is an allergy to tavegil.

Peritol (cyproheptadine), along with antihistamine, has a significant antiserotonin effect. It is often used in some forms of migraine to increase appetite.

Peritol syrup 2mg/5ml 100ml (Egis, Hungary)

Peritol tab. 4mg №20 (Egis, Hungary)

Pipolfen (promethazine) - a pronounced effect on the central nervous system, is used as an antiemetic and to potentiate anesthesia.

Pipolphen other 25mg №20 (Egis, Hungary)

Pipolfen solution for injections 50mg 2ml amp. №10 (Egis, Hungary)

Diprazine tab. 25mg #20

Phencarol (quifenadine) - has less antihistamine activity than diphenhydramine, but is also characterized by less penetration through the blood-brain barrier, which determines the lower severity of its sedative properties. In addition, fenkarol not only blocks histamine H1 receptors, but also reduces the content of histamine in tissues. Can be used in the development of addiction to other sedative antihistamines.

Fenkarol tab. 25mg №20 (Latvia)

Second generation antihistamines (non-sedating).

Unlike the first generation, they have almost no sedative and anticholinergic effects, do not penetrate the blood-brain barrier, do not reduce mental and physical activity, are not adsorbed with food in the gastrointestinal tract, have a high affinity for H1 receptors, and have a rapid therapeutic effect. . However, for them, a cardiotoxic effect was noted to varying degrees; when they are taken, constant monitoring of cardiac activity is required (appointed on an outpatient basis). They should not be taken by patients with disorders of the cardiovascular system, elderly patients.

The effect comes on quickly and for a longer time (delayed elimination).

When using drugs in therapeutic doses, a minimal sedative effect is observed. Some particularly sensitive individuals may experience moderate drowsiness, which does not require discontinuation of the drug.

The absence of tachyphylaxis (decrease in antihistamine activity) with prolonged use.

The cardiotoxic effect occurs due to the ability to block the potassium channels of the heart muscle, the risk of a cardiotoxic effect increases when antihistamines are combined with antifungals (ketoconazole and itraconazole), macrolides (erythromycin and clarithromycin), antidepressants (fluoxetine, sertraline and paroxetine), when drinking grapefruit juice and in patients with severe hepatic impairment.

There are no parenteral forms, only enteral and local dosage forms.

The most common second-generation antihistamines are:

Trexil (terfenadine) is the first second-generation antihistamine drug that does not have an inhibitory effect on the central nervous system, but with a significant cardiotoxic effect and an increased ability to cause fatal arrhythmias.

Trexil tab. 60mg №100 (Ranbaxi, India)

Gistalong (astemizole) is one of the longest acting drugs of the group (up to 20 days). It is characterized by irreversible binding to H1 receptors. Virtually no sedative effect, does not interact with alcohol.

Effective in chronic allergic diseases, with an acute process, its use is impractical. But the risk of developing serious heart rhythm disturbances, sometimes fatal, increases. Due to these dangerous side effects, the sale of astemizole in the United States and some other countries has been suspended.

Astemizole tab. 10mg #10

Histalong tab. 10mg №20 (India)

Semprex (acrivastine) is a drug with high antihistamine activity with a minimally pronounced sedative and anticholinergic effect. The therapeutic effect is achieved quickly, but for a short time.

Semprex caps. 8mg №24 (GlaxoWellcome, UK)

Fenistil (dimetendene) is closest to first-generation antihistamines, but differs from them in a significantly lesser sedative effect, higher antiallergic activity and duration of action than first-generation drugs. There is a gel for external use.

Claritin (loratadine) is one of the best-selling second-generation drugs. Its antihistamine activity is higher than that of astemizole and terfenadine, due to the greater strength of binding to peripheral H1 receptors.

There is no sedative effect, it does not potentiate the effect of alcohol. It practically does not interact with other drugs and does not have a cardiotoxic effect. It can be taken by drivers, children from 1 year old.

Claritin syrup 5mg/5ml 120ml (Schering-Plough, USA)

Claritin tab. 10mg №10 (Schering-Plough, USA)

Loratadine tab. 10mg #10

Agistam tab. 10mg #12

Third generation antihistamines (metabolites).

They are active metabolites of second-generation antihistamines. They do not have a sedative and cardiotoxic effect. In this regard, the drugs are approved for use by persons whose activities require increased attention.

Zyrtec, cetrin (cetirizine) is a highly selective blocker of peripheral H1 receptors. Cetirizine is almost not metabolized in the body, the rate of its excretion depends on the function of the kidneys. It penetrates well into the skin, and is effective in skin manifestations of allergies.

The effect appears 2 hours after ingestion and lasts 24 hours. Do not have a sedative and cardiotoxic effect in therapeutic doses. Be wary appoint in violation of kidney function.

Cetrin tab. 10mg No. 20 (Dr. Reddy's Laboratories, India)

Telfast (fexofenadine) is a metabolite of terfenadine. Does not metabolize in the body, does not interact with drugs, does not have a sedative effect and does not affect psychomotor activity. An effective and safest drug among antihistamines.

Telfast tab. 120mg №10 (Hoechst Marion Roussel)

Telfast tab. 180mg №10 (Hoechst Marion Roussel)

To suppress the development of an allergic reaction, it is necessary to take an antihistamine. Currently, there are a huge number of medicines from this group. All of them are divided by generations. The list of new generation antihistamines is quite wide and allows you to choose the best medicine for treatment. In the article we will take a closer look at the most effective medicines in this category.

General concept

Most people have heard of antihistamines, but not everyone knows what they are and how they work. This is the name of a group of drugs that can act on histamine receptors, a mediator of allergic reactions. Upon contact with an irritant, the human body begins to produce specific substances, among which histamine is the most active. When this substance “meets” with certain receptors, symptoms such as tearing, reddening of the skin, itching, and a rash develop.

Antiallergic drugs are able to block these receptors and, as a result, resist the appearance of unpleasant symptoms. Without them, negative processes in the body will continue.

Currently, there is a significant increase in the number of people suffering from this or that type of allergy. An inadequate reaction of the immune system can develop against the background of disorders of the endocrine or nervous system, but most often the cause is external irritants: plant pollen, wool, dust, chemicals, some foods.

Treatment with antihistamines

In most cases, allergies cannot be completely cured. Medicines that affect histamine receptors will help get rid of unpleasant symptoms or prevent their occurrence.

To date, there are several generations of these medicines. And if the first antiallergic drugs brought not only long-awaited relief, but also many side effects, then the new generation antihistamines, the list of which we will consider below, are practically devoid of drawbacks and have practically no contraindications for use.

Medicines of this category are prescribed in the following cases:

• with year-round or seasonal rhinitis;
• with a negative reaction to flowering plants;
• when symptoms of food and drug allergies occur;
• with atopic dermatitis;
• with urticaria and itching of the skin;
• with bronchial asthma;
• with angioedema;
• with allergic conjunctivitis.

New generation antihistamines: an overview

Among all antiallergic medicines, the latest generation of drugs are considered the safest. They are prodrugs, which means that when they enter the body, the substances contained in the composition are converted into active metabolites. Such agents act only on histamine H-1 receptors and do not adversely affect the central nervous system.

The list of new generation antihistamines is small, however, compared with the precursor drugs, they can be prescribed to almost all patients suffering from various types of allergic reactions. Such funds allow you to quickly stop the already manifested symptoms and do not have a toxic effect on the heart. The following drugs are popular:

• "Cetirizine".
• "Fexofenadine".
• "Erius".
• "Fexofast".
• "Ksizal".
• "Levocetirizine".
• "Desal".
• "Caesera".
• "Desloratadine".
• "Kestin".

Features of drugs

The most common antiallergic drugs of the latest generation are those that contain fexofenadine in their composition. The substance belongs to selective inhibitors of H-1 histamine receptors and is able to stabilize mast cell membranes. The component inhibits the process of migration of leukocytes to the focus of the inflammatory process.

4th generation antihistamines based on cetirizine are considered one of the most effective. They are able to quickly stop the development of skin allergic reactions. They have a pronounced antipruritic and antiexudative effect.

Each of the modern anti-allergy drugs is prescribed only after the examination. The dosage regimen and duration of use is determined strictly individually.

"Erius": a description of the medication

An antihistamine based on desloratadine is produced by a branch of the pharmaceutical company Schering-Plough Corporation / USA in Belgium. You can buy medicines in tablet form and in the form of syrup. In addition to the main active ingredient, the tablets contain titanium dioxide, talc, calcium hydrogen phosphate dihydrate, lactose monohydrate, white wax, corn starch, microcrystalline cellulose.

The syrup contains such auxiliary components as citric acid, sorbitol, sodium benzoate, propylene glycol, sodium citrate dihydrate, sucrose. Tablets are packaged in packs of 7 and 10 pieces per blister. The syrup has the appearance of a yellow liquid and is available in 60 and 120 ml bottles.

Indications for appointment

Tablets "Erius" instructions for use recommend taking with seasonal rhinitis, lacrimation, itching of the nasal mucosa, seasonal pollinosis, chronic idiopathic urticaria. As prescribed by a specialist, the medication can also be used for other allergic conditions. For example, many patients say that Erius copes well with signs of neurodermatitis, food allergies, atopic dermatitis.

As part of complex therapy, an antihistamine can be taken for chicken pox, pink lichen, scabies and pseudo-scabies. "Erius" will effectively eliminate severe itching and help you fall asleep.

In pediatric practice, an antiallergic drug is used in the form of a syrup. The manufacturer claims that it can be given to babies older than 1 year. The dosage will depend on the age category. Erius tablets are suitable for adult patients and children from 12 years of age. Instructions for use recommends taking 1 tablet (5 mg) per day.

"Cetirizine": reviews

Modern antiallergic drugs are able to stop the development of the disease at the earliest stages. This is extremely important in severe allergic reactions. That is why many experts in the list of new generation antihistamines in the first place is "Cetirizine". An agent based on the active ingredient of the same name quickly relieves bronchospasm, attacks of bronchial asthma, and prevents the development of Quincke's edema. In addition, the medication will be effective for hives, pollinosis, hay fever, eczema, allergic dermatitis.

The antihistamine drug "Cetirizine" is available in the form of drops for oral administration, syrup and tablets. 1 ml of liquid solution contains 10 mg of cetirizine. One tablet contains the same amount of active substance. A noticeable effect from the use of an H-1 histamine receptor blocker can be seen an hour after administration. The duration of action is 24 hours. In bronchial asthma, it is used in combination with the bronchodilator drug Fenspiride.

Contraindications and side effects

Treatment with "Cetirizine" should be abandoned in case of hypersensitivity to the main component and hydroxyzine. It is forbidden to prescribe an antihistamine to people who are on hemodialysis or have kidney failure, during breastfeeding and pregnancy. Contraindications are also conditions associated with lactase deficiency, glucose-galactose malabsorption and lactose intolerance. With caution take "Cetirizine" simultaneously with barbiturates, ethanol-containing drugs and opioid analgesics.

Excellent tolerance is a huge advantage of the drug. Side effects while taking tablets, drops or syrup are extremely rare. This is mainly due to an overdose of the active substance. In such cases, the following symptoms may develop:

• dizziness;
• migraine;
• nervous excitement;
• tachycardia;
• insomnia;
• urinary retention;
• myalgia;
• skin rashes, eczema.

What is Kestin?

Another effective histamine receptor blocker is Kestin. It is produced by the pharmaceutical company Nycomed Danmark ApS (Denmark). Modern antiallergic agent is quite expensive. The average price of tablets (10 pieces per pack) is 380-400 rubles.

What is the composition of this medicine? Ebastine is the main component that blocks histamine H-1 receptors. The substance quickly eliminates spasms of the smooth muscles of the bronchi, reduces exudation, stops the manifestation of skin allergic reactions. "Kestin" is available in the form of tablets, which may contain various amounts of ebastine (10 or 20 mg) and syrup. The manufacturer also offers lozenges containing 20 mg of the active substance.

Who suits?

Any 4th generation antihistamines, including Kestin, can be taken only after consultation with an allergist. Most often, the drug is prescribed to adult patients. The instruction allows the use of tablets in pediatric practice, but only if the child is over 12 years old. Lozenges are prescribed only from the age of 15. The syrup can be used to treat children from 6 years of age.

"Kestin" effectively eliminates the symptoms of year-round and seasonal rhinitis of various origins, conjunctivitis, urticaria, Quincke's edema. The drug relieves symptoms caused by drug, food, insect allergies.

It is worth refraining from using "Kestin" during pregnancy, lactation, with intolerance to ebastine or other components of the drug. Lozenges are not prescribed for patients suffering from phenylketonuria. Under the supervision of a physician, an antihistamine is used for ischemic disease, hypokalemia, renal and hepatic insufficiency.

Description of the drug "Ksizal"

If necessary, symptomatic treatment of allergic skin reactions, urticaria, rhinorrhea, Quincke's edema, hay fever, many prefer the modern remedy "Ksizal". The cost of one package is 420-460 rubles. The drug is produced at pharmaceutical factories in Belgium, Switzerland and Italy.

The main active component of Xyzal is levocetirizine. The substance has pronounced anti-allergic properties. The active metabolite is able to prevent the development of allergies or significantly alleviate the course of the pathological condition. The substance reduces the permeability of the vascular walls, blocks the activity of cytokines and inflammatory mediators, and inhibits the movement of eosinophils. The clinical effect of the drug persists for 24 hours.

When are they assigned?

In the list of new allergy drugs, Xyzal occupies the first position due to its quick effect and safety. A modern drug has practically no contraindications to the appointment and rarely provokes the development of side effects. It is recommended to use it for a variety of allergic reactions: Quincke's edema, hay fever, allergic dermatitis, itching, sneezing, nasal congestion against the background of seasonal or year-round runny nose.

In the form of drops, "Ksizal" can be prescribed to babies from 2 years old. The tablets are suitable for use in children from 6 years of age and adults. The drug received many positive recommendations related to ease of use. One tablet of "Ksizal" can relieve allergy symptoms for a whole day.

"Levocetirizine" for allergies

The drug "Levocetirizine" is a cheaper analogue of "Ksizal". The cost of one package (10 tablets) ranges from 230-250 rubles. Also, the medicine can be purchased in the form of syrup and drops.

The active substance of the drug is able to block the endings of H-1 histamine receptors, thereby preventing the development of an inadequate response of the immune system. Allergy tablets "Levocetirizine" will be effective for hay fever, allergic dermatitis, seasonal and chronic rhinitis, lacrimation, sneezing, angioedema, urticaria.

The drug is not used to treat children under 6 years of age, during pregnancy and breastfeeding, with hypersensitivity to the components in the composition and severe renal failure.

The drug "Bamipin"

The list of new generation antihistamines includes agents intended for systemic use. However, in some cases, local medication is also required. To cope with skin manifestations of allergies, you should use special gels. One of these external medicines is Bamipin. It can be used already with the appearance of the first symptoms of urticaria, an allergic reaction to insect bites, itching of the skin, thermal burns. The drug is also available in the form of tablets.

Today we will talk about the new, latest generation antihistamines, their list, how effective they are, pharmacological action, how to take, side effects and much more.

Groups of antihistamines

The prevalence of allergic diseases among the population is steadily increasing every year.

In order to stop the symptoms of allergies, improve well-being and completely eliminate the likelihood of severe and sometimes fatal complications, the use of antiallergic drugs is required.

Second generation antihistamines

There is no pronounced sedative effect and most of these drugs have a prolonged action, that is, they can be taken once a day.

The appointment of such drugs should be carried out with caution, as they have a cardiotoxic effect. That is, their intake is completely contraindicated for those who have a history of cardiovascular pathologies.

An example is a drug.

Pharmacological action of drugs

Antihistamines from the latter group are selective in their action - they act only on H1 - histamine receptors.

The anti-allergic effect on the body occurs due to several changes.

These medicines:

• They inhibit the production of mediators (including cytokines and chemokines) that affect systemic allergic inflammation;
• Reduce the total number and change the functioning of adhesion molecules;
• Reduce chemotaxis. This term refers to the release of leukocytes from the vascular bed and their penetration into the damaged tissue;
• Inhibit the activation of eosinophils;
• Prevent the production of superoxide radical;
• Reduce bronchial hypersensitivity.

All the changes that occur under the action of the latest generation of antihistamines lead to a decrease in the permeability of the walls of blood vessels. As a result, swelling, hyperemia, itching of the skin and mucous membranes disappear.

The absence of an effect on histamine receptors of types 2 and 3 determines the absence of pronounced side changes in the form of drowsiness and toxic effects on the heart muscle.

The latest anti-allergic drugs do not interact with choline receptors, and therefore patients are not bothered by dry mouth and blurred vision.

Due to the high anti-inflammatory and anti-allergic effect, antihistamines of the third group can be prescribed when necessary.

Possible side effects

Patients taking the latest generation of antihistamines rarely notice adverse reactions. But it cannot be said that they do not exist at all.

When treating with these drugs, the occurrence of:

• headaches;
• Increased fatigue;
• Periodic dizziness;
• Severe drowsiness or vice versa insomnia;
• hallucinations;
• tachycardia;
• Dryness in the mouth;
• Dyspeptic disorders in the form of nausea, colic and abdominal pain, vomiting;
• Pain in different muscle groups;
• Rash on the skin.

Very rarely, with prolonged treatment, hepatitis has developed. With a predisposition to allergies, the likelihood of body itching, anaphylactic reactions, including Quincke's edema, is increased.

List of drugs

The newest generation of antihistamines include:

• fexofenadine;
• Levocetirizine;
• cetirizine;
• Desloratadine;
• Hifenadine;

It must be remembered that the funds listed are also available under other names, but their main active ingredient does not change.

Norastemizol and a number of other drugs, which are still better known abroad, are under development.

Indications for use

The effectiveness of the treatment of allergies is largely determined by the correct selection of the drug, which must be entrusted to the doctor.

Third generation antiallergic medicines are used to treat patients with:

1. Seasonal and year-round;
2. Conjunctivitis that occurs under the influence of allergens;
3. contact dermatitis;
4. Urticaria of acute and chronic course;

The latest generation drugs can be used in the course and after the elimination of acute symptoms of anaphylactic shock, drug allergy, Quincke's edema.

General contraindications to their appointment is considered only intolerance by the patient of the main or additional components of the drug.

Fexofenadine

The drug is available in two dosage forms. Tablets have a dosage of 30, 60, 120 and 180 mg.

The suspension contains 6 mg of the main anti-allergic substance in one ml.

Allergy symptoms begin to subside about an hour after oral ingestion.

The maximum effect begins to appear after 6 hours and then keeps at the same level during the day.

You should take the medicine, observing the following rules:

• Patients over 12 years of age need a daily dose of the drug at a dose of 120 and 180 mg. The tablet is drunk once a day, preferably at the same time.
• From 6 to 11 years, the daily dose is 60 mg, but it is recommended to divide it into two doses.
• The tablet does not need to be chewed. Drink it with one glass of clean water.
• The duration of therapy depends on the type of allergic reaction and its severity.

Fexofenadine was successfully taken by a group of patients for a month or more without the development of symptoms of its intolerance.

The drug is best to cope with allergic rhinitis, it is recommended to prescribe it for hay fever, rashes on the body and urticaria.

Fexofenadine is not prescribed if the child is under 6 years of age. Caution in the treatment of this drug should be shown to those who have a history of renal or hepatic pathology.

The components of the drug pass into breast milk, and therefore it cannot be used during lactation.

How Fexofenadine acts on the course of pregnancy has not been clarified, therefore this remedy is prescribed to expectant mothers only in exceptional cases.

It is distinguished by the most rapid development of anti-allergic effects on the body - some patients note a decrease in allergy symptoms within 15 minutes after ingestion.

In most people taking the drug, improvement in well-being occurs after 30-60 minutes.

The maximum concentration of the main active substance is determined within two days. The drug passes into breast milk.

Levocetirizine is prescribed for the treatment of various forms of allergic rhinitis, the drug helps with, urticaria and.

Accept it, guided by the following rules:

• The tablet form is prescribed for children over 6 years of age and adults.
• Per day, you need 5 mg of the drug, which are contained in one tablet. It is drunk regardless of when a meal is planned, but the drug should definitely be washed down with a glass of water.
• The drug in drops from 6 years old is prescribed 20 drops per day. If the age of the child is less, then the dosage is selected depending on his weight.
• The duration of the course of treatment depends on the type and severity of the allergic reaction. Patients with pollinosis Levocetirizine can be prescribed for up to 6 months. In chronic allergies, the drug is sometimes continued for a year. In the event that possible contact with the allergen is expected, the medicine can be drunk within a week.

Levocetirizine is not prescribed in pediatric practice for children under two years of age. Contraindications to its use are also considered pregnancy, severe renal failure, congenital pathologies of carbohydrate metabolism.

For patients with impaired renal function, the dose of the drug is selected after passing the tests. In cases of mild to moderate pathology, a dose of 5 mg can be drunk once every two or three days.

Analogues of Levocetirizine are considered -, Alerzin, Aleron Neo, L-cet, Glenset, Zilola.

cetirizine

Available in the form of tablets, drops, syrup. The drug is a metabolite of hydroxyzine.

Cetirizine relieves itching well, so its action is optimal in the treatment of urticaria and itchy dermatoses.

The agent shows high efficiency in eliminating the symptoms of acute and chronic rhinitis caused by the influence of allergens, in particular ragweed.

The medicine eliminates the symptoms of allergic conjunctivitis - lacrimation, itching, redness of the sclera.

The anti-allergic effect occurs after two hours and lasts for at least one day.

The drug is prescribed depending on the age of the patient:

Adjust the dose of the drug is necessary for patients with impaired renal function.

Cetirizine treatment is contraindicated during breastfeeding, with congenital disorders in the metabolism of carbohydrates, with individual hypersensitivity.

This medicine should be used with caution in those who have a history of epilepsy and convulsions.

During pregnancy, the drug is prescribed only in extreme cases.

The most famous analogues of Cetirizine include Rolinoz, Allertec, Amertil, Cetrinal. skin rashes and urticaria, hay fever.

The active substance of the drug retains its anti-allergic activity in the body throughout the day.

Tableting form is prohibited for use up to 12 years. Children from one year of age should receive the drug in the form of a syrup.

Hifenadine (trade name Phencarol)

Available in the form of tablets and as a solution for intramuscular injection.

Oral administration provides the onset of anti-allergic action in an hour, injection administration leads to a decrease in allergy symptoms in half an hour.

Hifenadine and its analogues are prescribed for:

• Dermatoses accompanied by itching and skin irritation;
• Chronic and acute urticaria;
• Food and;
• hay fever, allergies to ragweed;
• Allergic conjunctivitis and rhinitis;
• Angioedema.

The daily dose of the drug for adults is up to 200 mg, it is divided into three doses.

Dosage for children is prescribed depending on their age and type of allergic reaction. Treatment should last from 10 to 20 days.

Hifenadine is contraindicated throughout pregnancy, children under three years of age, during the lactation period. Trade names of the drug Fenkarol-Olaine, Fenkarol.

An allergist should prescribe any antihistamine medication. A qualified doctor takes into account not only the severity of the allergic reaction, but also the age of the patient, the presence of others, including chronic diseases.

Self-treatment often causes the development of severe forms of allergies and this should always be remembered.

1st generation antihistamines

According to their chemical structure, these drugs are divided into the following groups:

1) derivatives of aminoalkyl ethers - diphenhydramine (diphenhydramine, benadryl, alphadryl), amidryl, etc.
2) derivatives of ethylenediamine - antergan (suprastin), allergan, dehistine, mepyramine, etc.
3) derivatives of phenothiazines - promethazine (pipolphen, diprazine, phenergan), doxergan, etc.
4) derivatives of alkylamines - pheniramine (trimeton), triprolidine (actadil), dimetindine (fenostil), etc.
5) derivatives of benzhydryl ethers - clemastine (tavegil).
6) piperidine derivatives - cyproheptadine (peritol), cyprodine, astonine, etc.
7) quinuclidine derivatives - quifenadine (fencarol), sequifenadine (bicarfen).
8) piperazine derivatives - cyclizine, meclizine, chlorcyclizine, etc.
9) alphacarboline derivatives - diazolin (omeril).

Suprastin(chloropyramine) has a pronounced antihistamine and M-anticholinergic effect, penetrates the blood-brain barrier, causes drowsiness, general weakness, dry mucous membranes and increases the viscosity of secretions, irritation of the gastrointestinal mucosa, headache, dry mouth, urinary retention, tachycardia, glaucoma. Assigned inside 2-3 times a day, intramuscularly.

promethazine(pipolfen, diprazine) has a strong antihistamine activity, is well absorbed and easily penetrates the blood-brain barrier with different routes of administration, and therefore has significant sedative activity, enhances the effect of narcotic, hypnotic, analgesic and local anesthetics, lowers body temperature, prevents and soothes vomiting. It has a moderate central and peripheral anticholinergic effect. When administered intravenously, it can cause a drop in systemic arterial pressure, collapse. They are administered orally and intramuscularly.

clemastine(tavegil) is one of the most common and effective antihistamines of the 1st generation, it selectively and actively blocks H1 receptors, acts longer (8-12 hours), poorly penetrates the blood-brain barrier, therefore it does not have sedative activity and does not causes a drop in blood pressure. It is recommended for use in acute allergic reactions parenterally (anaphylactic shock, severe forms of allergic dermatosis).

Diazolin(omeril) has less antihistamine activity, but practically does not penetrate the blood-brain barrier and does not cause sedative and hypnotic effects, it is well tolerated.

Fenkarol(quifenadine) is an original antihistamine drug, moderately blocks H1 receptors and reduces the content of histamine in tissues, has a low lipophilicity, does not penetrate the blood-brain barrier and does not have sedative and hypnotic effects, does not have adrenolytic and anticholinergic activity, has an antiarrhythmic effect. Children under the age of 3 years are prescribed 0.005 g, from 3 to 12 years old - 0.01 g each, over 12 years old - 0.025 g 2-3 times a day.

Peritol(cyproheptadine) moderately blocks H1 receptors, has a strong antiserotonin activity, as well as an M-anticholinergic effect, penetrates the blood-brain barrier and has a pronounced sedative effect, reduces the hypersecretion of ACTH and somatotropin, increases appetite, and reduces the secretion of gastric juice. It is prescribed for children from 2 to 6 years old - 6 mg in three doses, over 6 years old - 4 mg 3 times a day.

Comparative characteristics of the most common antihistamines of the 1st generation are presented in Table. 3.

Table 3 1st generation antihistamines recommended for the treatment of allergic pathology in children

Features of the pharmacological effects of 1st generation antihistamines

As shown in Table. 3, antihistamines of the first generation, by noncompetitively and reversibly inhibiting H1 receptors, block other receptor formations, in particular, cholinergic muscarinic receptors and thus have an M1 cholinergic effect. Their atropine-like action can cause dry mucous membranes and exacerbate bronchial obstruction. To achieve a pronounced antihistamine effect, high concentrations of these drugs in the blood are required, which requires the appointment of large doses. In addition, these compounds act quickly after administration, but for a short time, which requires their repeated use (4-6 times) during the day. It is important to note that antihistamines have an effect on the central nervous system, penetrating the blood-brain barrier, and can cause blockade of H1 receptors in cells of the central nervous system, which causes their undesirable sedative effect.

The most important property of these drugs, which determines the ease of penetration through the blood-brain barrier, is their lipophilicity. The sedative effects of these drugs, ranging from mild drowsiness to deep sleep, can often occur even at their usual therapeutic doses. Essentially, all 1st generation antihistamines have a pronounced sedative effect to one degree or another, most noticeable in phenothiazines (pipolphen), ethanolamines (diphenhydramine), piperidines (peritol), ethylenediamines (suprastin), to a lesser extent - in alkylamines and benzhydryl ether derivatives (clemastine, tavegil). The sedative effect is practically absent in quinuclidine derivatives (fencarol).

Other undesirable manifestations of the action of these drugs on the central nervous system are coordination disorders, dizziness, a feeling of lethargy, and a decrease in the ability to concentrate. Some 1st generation antihistamines exhibit the properties of local anesthetics, have the ability to stabilize biomembranes and, by prolonging the refractory phase, can cause cardiac arrhythmias. Some drugs of this group (pipolfen), potentiating the effects of catecholamines, cause fluctuations in blood pressure (Table 3).

Among the undesirable effects of these drugs, it should also be noted an increase in appetite, most pronounced in piperidines (peritol) and the occurrence of functional disorders of the gastrointestinal tract (nausea, vomiting, discomfort in the epigastric region), more often manifested when taking ethylenediamines (suprastin, diazolin). For most 1st generation antihistamines, peak concentrations are reached after 2 hours. However, a negative characteristic of H1-antagonists of the 1st generation is the rather frequent development of tachyphylaxis - a decrease in therapeutic efficacy during their long-term use (Table 4).

Table 4 Unwanted side effects of first generation antihistamines:

• 1. Pronounced sedative and hypnotic effect
• 2. Negative effect on the central nervous system - impaired coordination, dizziness, decreased concentration
• 3. M-cholinergic (atropine-like) action
• 4. Development of tachyphylaxis
• 5. Short duration of action and repeated use

Table 5 Limitations of the clinical use of first-generation antihistamines:

• astheno-depressive syndrome;
• bronchial asthma, glaucoma;
• spastic phenomena in the pyloric or duodenal areas;
• atony of the intestines and bladder;
• all activities that require active attention and quick response

2nd generation antihistamines

Antihistamines of the 2nd generation have been widely used in allergological practice in recent years. These drugs have a number of advantages over 1st generation drugs (Table 6)

Table 6 Effects of second generation antihistamines

• 1. Have very high specificity and affinity for H1 receptors
• 2. Do not cause blockade of other types of receptors
• 3. Do not have M-anticholinergic action
• 4. In therapeutic doses, they do not penetrate the blood-brain barrier, do not have sedative and hypnotic effects
• 5. They have a fast onset of action and a pronounced duration of the main effect (up to 24 hours)
• 6. Well absorbed from the gastrointestinal tract
• 7. No relationship has been established between drug absorption and food intake
• 8. Can be applied at any time
• 9. Do not cause tachyphylaxis
• 10. Easy to use (1 time per day)

Table 7 2nd generation antihistamines recommended for the treatment of allergic pathology in children

Claritin (loratadine) is the most common antihistamine drug, it has a specific blocking effect on H1 receptors, for which it has a very high affinity, does not have anticholinergic activity and therefore does not cause dry mucous membranes and bronchospasm.

Claritin quickly acts on both phases of the allergic reaction, inhibits the production of a large number of cytokines, directly inhibits the expression of cell adhesion molecules (ICAM-1, VCAM-1, LFA-3, P-selectins and E-selectins), reduces the formation of leukotriene C4, thromboxane A2 , factors of eosinophil chemotaxis and platelet activation. Thus, claritin effectively prevents the formation of allergic inflammation and has a pronounced antiallergic effect (Leung D., 1997). These properties of claritin were the basis for its use as a basic remedy in the treatment of such allergic diseases as allergic rhinitis, conjunctivitis and hay fever.

Claritin also helps to reduce bronchial hyperreactivity, increases forced expiratory volume (FEV1) and peak expiratory flow, which determines its beneficial effect in bronchial asthma in children.

Claritin is effective and can currently be used as an alternative anti-inflammatory therapy, especially in mild persistent bronchial asthma, as well as in the so-called cough variant of bronchial asthma. In addition, this drug does not penetrate the blood-brain barrier, does not affect the activity of the NCS and does not potentiate the action of sedatives and alcohol. The sedative effect of claritin is not more than 4%, that is, it is detected at the placebo level.

Claritin does not have a negative effect on the cardiovascular system, even at concentrations exceeding the therapeutic dose by 16 times. Apparently, this is determined by the presence of several pathways of its metabolism (the main pathway is through the oxygenase activity of the CYP3A4 isoenzyme of the cytochrome P-450 system and the alternative pathway is through the CYP2D6 isoenzyme), so claritin is compatible with macrolides and antifungal drugs imidazole derivatives (ketoconazole, etc.) , as well as with a number of other medicines, which is crucial when using these medicines simultaneously.

Claritin is available in tablets of 10 mg and in syrup, 5 ml of which contains 5 mg of the drug.

Claritin tablets are prescribed for children from the age of 2 years in the appropriate age dosage. The maximum plasma level of the drug is reached within 1 hour after ingestion, which ensures a rapid onset of effect. Food intake, impaired liver and kidney function do not affect the pharmacokinetics of claritin. The release of claritin occurs after 24 hours, which allows you to take it 1 time per day. Long-term use of Claritin does not cause tachyphylaxis and addiction, which is especially important in the treatment of itchy forms of allergic dermatosis (atopic dermatitis, acute and chronic urticaria and strophulus) in children. The effectiveness of claritin was studied by us in 147 patients with various forms of allergic dermatoses with a good therapeutic effect in 88.4% of cases. The best effect was obtained in the treatment of acute and especially chronic urticaria (92.2%), as well as atopic dermatitis and strophulus (76.5%). Given the high efficacy of claritin in the treatment of allergic dermatosis and its ability to inhibit the production of leukotrienes, we studied its effect on the activity of eicosanoid biosynthesis by peripheral blood granulocytes in patients with atopic dermatitis. The biosynthesis of prostanoids by peripheral blood leukocytes was studied by the radioisotope method using labeled arachidonic acid under in vitro conditions.

During treatment with claritin in patients with atopic dermatitis, a decrease in the biosynthesis of the studied eicosanoids was found. At the same time, the biosynthesis of PgE2 decreased most significantly - by 54.4%. The production of PgF2a, TxB2 and LTV4 decreased by an average of 30.3%, and prostacyclin biosynthesis decreased by 17.2% compared with the level before treatment. These data indicate a significant effect of claritin on the mechanisms of atopic dermatitis formation in children. It is obvious that the decrease in the formation of pro-inflammatory PTV4 and pro-aggregate TxB2 against the background of relatively unchanged prostacyclin biosynthesis is an important contribution of claritin to the normalization of microcirculation and the reduction of inflammation in the treatment of atopic dermatitis. Therefore, the revealed regularities of the effects of claritin on the mediator functions of eicosanoids should be taken into account in the complex therapy of allergic dermatoses in children. Our data allow us to conclude that the appointment of claritin is especially appropriate for allergic skin diseases in children. With dermorespiratory syndrome in children, claritin is also an effective drug, as it can simultaneously affect the skin and respiratory manifestations of allergies. The use of claritin in dermorespiratory syndrome for 6-8 weeks helps to improve the course of atopic dermatitis, reduce asthma symptoms, optimize external respiration, reduce bronchial hyperreactivity and reduce symptoms of allergic rhinitis.

Zyrtec(Cetirizine) is a pharmacologically active non-metabolizable product that has a specific blocking effect on H1 receptors. The drug has a pronounced antiallergic effect, as it inhibits the histamine-dependent (early) phase of the allergic reaction, reduces the migration of inflammatory cells and inhibits the release of mediators involved in the late phase of the allergic reaction.

Zirtek reduces the hyperreactivity of the bronchial tree, does not have an M-anticholinergic effect, therefore it is widely used in the treatment of allergic rhinitis, conjunctivitis, hay fever, and also when they are combined with bronchial asthma. The drug does not adversely affect the heart.

Zyrtec is available in tablets of 10 mg and in drops (1 ml = 20 drops = 10 mg), characterized by the rapid onset of the clinical effect and prolonged action due to its insignificant metabolism. It is prescribed for children from the age of two: from 2 to 6 years old, 0.5 tablets or 10 drops 1-2 times a day, for children 6-12 years old - 1 tablet or 20 drops 1-2 times a day.

The drug does not cause tachyphylaxis and can be used for a long time, which is important in the treatment of allergic skin lesions in children. Despite the indications of the absence of a pronounced sedative effect when taking Zyrtec, in 18.3% of observations we found that the drug, even at therapeutic doses, caused a sedative effect. In this regard, caution should be exercised when using Zirtek with sedatives because of the possible potentiation of their action, as well as in the pathology of the liver and kidneys. A positive therapeutic effect of the use of Zirtek was obtained by us in 83.2% of cases of treatment of allergic dermatoses in children. This effect was especially pronounced in itching forms of allergic dermatoses.

Kestin(Ebastine) has a pronounced selective H1-blocking effect, without causing anticholinergic and sedative effects, is rapidly absorbed and almost completely metabolized in the liver and intestines, turning into the active metabolite carebastin. Taking kestin with fatty foods increases its absorption and the formation of carebastin by 50%, which, however, does not affect the clinical effect. The drug is available in tablets of 10 mg and is used in children over 12 years of age. A pronounced antihistamine effect occurs 1 hour after ingestion and lasts 48 hours.

Kestin is effective in the treatment of allergic rhinitis, conjunctivitis, pollinosis, as well as in the complex therapy of various forms of allergic dermatosis - especially chronic recurrent urticaria and atopic dermatitis.

Kestin does not cause tachyphylaxis and can be used for a long time. At the same time, it is not recommended to exceed its therapeutic doses and be careful when prescribing ketin in combination with macrolides and some antifungal drugs, since it can cause a cardiotoxic effect. Despite the spread of such 2nd generation drugs as terfenadine and astemizole, we do not recommend their use in the treatment of allergic diseases in children, since some time after the start of using these drugs (since 1986), clinical and pharmacological data appeared, indicating the damaging effect of these drugs on the cardiovascular system and liver (cardiac arrhythmias, prolongation of the Q-T interval, bradycardia, hepatotoxicity). Mortality was established in 20% of patients treated with these drugs. Therefore, these drugs should be used with caution, not exceeding the therapeutic dose and not used in patients with hypokalemia, cardiac arrhythmias, congenital prolongation of the QT interval, and especially in combination with macrolides and antifungal drugs.

Thus, in recent years, the pharmacotherapy of allergic diseases in children has been replenished with a new group of effective H1 receptor antagonists, devoid of a number of negative properties of first-generation drugs. According to modern ideas, an ideal antihistamine drug should quickly show an effect, act for a long time (up to 24 hours) and be safe for patients. The choice of such a drug should be carried out taking into account the individuality of the patient and the characteristics of the clinical manifestations of allergic pathology, as well as taking into account the laws of the pharmacokinetics of the drug. Along with this, when assessing the priority of prescribing modern H1 receptor antagonists, special attention should be paid to the clinical efficacy and safety of such drugs for the patient. The selection criteria for second generation antihistamines are shown in Table 8.

Table 8 Criteria for choosing second-generation antihistamines

Our studies and clinical observations indicate that such a second-generation antihistamine that satisfies the above conditions, is clinically effective and safe in the treatment of allergic diseases in children, is primarily claritin, and then - zyrtec.

Currently, in the special literature, opinions regarding which antiallergic drugs should be attributed to the second and third generation diverge. In this regard, the list of 2nd generation antihistamines will have its own characteristics, depending on what point of view modern pharmacists adhere to.

What are the criteria for classifying antihistamines in the second group?

According to the first point of view, second-generation drugs are all those anti-allergic drugs that are devoid of sedation, because they do not penetrate the brain through the blood-brain barrier.

The second and most common point of view is that the second generation of antihistamines should include only those that, although they do not affect the nervous system, are capable of causing changes in the heart muscle. Medicines that do not act on the heart and nervous system are classified as third-generation antihistamines.

According to the third point of view, only one drug with antihistamine properties, ketotifen, belongs to the second generation, because it has a membrane-stabilizing effect. And all those drugs that stabilize the mast cell membrane, but do not cause sedation, make up the third generation of antihistamines.

Why are antihistamines given this name?

Histamine is the most important substance, which is mainly found in mast cells of the connective tissue and blood basophils. Being released under the influence of various factors from these cells, it connects to the H 1 and H 2 receptors:

• H 1 receptors, when interacting with histamine, cause bronchospasm, contraction of smooth muscles, dilate capillaries and increase their permeability.
• H 2 receptors stimulate an increase in acidity in the stomach, affect the heart rate.

Indirectly, histamine can cause severe itching by stimulating the release of catecholamines from adrenal cells, increase the secretion of the salivary and lacrimal glands, and also accelerate intestinal motility.

Antihistamines bind to H 1 and H 2 receptors and block the action of histamine.

List of drugs of the second group

According to the most common classification of antihistamines, the second generation includes:

• dimethindene,
• loratadine,
• ebastine,
• cyproheptadine,
• azelastine,
• acrivastine.

All these drugs do not penetrate the brain, so they do not cause a sedative effect. However, the possible development of cardiotoxic action limits the use of this group of drugs in the elderly and those who suffer from heart disease.

Enhances myocardial damage in the treatment of second-generation antihistamines, the simultaneous use of antifungal agents and some antibiotics with them, for example, clarithromycin, erythromycin, itraconazole and ketoconazole. You should also refrain from drinking grapefruit juice and antidepressants.

Dimetinden (Fenistil)

Available in the form of drops, gel and capsules for oral administration. It is one of the few drugs that can be used in children of the first year of life, with the exception of the neonatal period.

Fenistil is well absorbed inside and has a pronounced anti-allergic effect, lasting after 1 dose for about 6-11 hours.

The drug is effective for skin itching, eczema, drug and food allergies, insect bites, itchy dermatoses and exudative-catarrhal diathesis in children. Its other purpose is the removal of household and mild sunburns.

Application features. It is one of the few second-generation drugs that still crosses the blood-brain barrier, so it can slow down the reaction when driving. In this connection, it should be prescribed with extreme caution to drivers, and even more so not to be used during work that requires a quick reaction.

When applying the gel to the skin, it is necessary to protect this area from exposure to direct sunlight.

Dimetindene is contraindicated during the first trimester of pregnancy and in the neonatal period. It is used with caution in the second and third trimesters of pregnancy, with prostate adenoma, angle-closure glaucoma.

Loratadine (claritin, lomilan, lotaren)

Like other drugs in this group, it effectively treats all kinds of allergic diseases, especially allergic rhinitis, conjunctivitis, nasopharyngitis, angioedema, urticaria, endogenous itching. The drug is available in the form of tablets and syrup for oral administration, and is also part of multicomponent antiallergic gels and ointments for local treatment.

Effective for pseudo-allergic reactions, pollinosis, urticaria, itchy dermatoses. As an aid, it is prescribed for bronchial asthma.

Application features. May cause sedation in the elderly and is not recommended during pregnancy and breastfeeding. Many drugs reduce the effectiveness of loratadine or increase its side effects, so you should always consult with your doctor before taking it.

Ebastin (Kestin)

It also belongs to the group of second-generation antihistamines. Its distinguishing feature is the absence of interaction with ethanol, so it is not contraindicated in the use of drugs containing alcohol. Simultaneous administration with ketoconazole increases the toxic effect on the heart, which can lead to fatal consequences.

Ebastin is prescribed for allergic rhinitis, urticaria and other diseases accompanied by excessive release of histamine.

Cyproheptadine (peritol)

This drug for the treatment of allergic reactions can be prescribed to children from 6 months. Like other drugs in this group, cyproheptadine has a strong and lasting effect, eliminating allergy symptoms. A distinctive feature of peritol is the relief of migraine headaches, a calming effect, and a decrease in the excess secretion of somatotropin in acromegaly. Cyproheptadine is prescribed for toxicoderma, neurodermatitis, in the complex therapy of chronic pancreatitis, serum sickness.

Azelastine (allergodil)

This drug copes well with such types of allergy manifestations as allergic rhinitis and conjunctivitis. Available as a nasal spray and eye drops. In pediatrics, it is prescribed for children from 4 years old (eye drops) and from 6 years old (spray). The duration of the course of treatment with azelastine on the recommendation of a doctor can last up to 6 months.

From the nasal mucosa, the drug is well absorbed into the general circulation and has a systemic effect on the body.

Acrivastine (semprex)

The drug penetrates poorly through the blood-brain barrier, therefore it does not have a sedative effect, however, drivers of vehicles and those whose work requires quick and accurate actions should refrain from taking it.

Acrivastine differs from other representatives of this group in that it begins to act within the first 30 minutes, and the maximum effect on the skin is observed already 1.5 hours after administration.

Drugs of the second group, about which there is disagreement in the scientific community

Mebhydrolin (diazolin)

Most experts attribute diazolin to the first generation of antihistamines, while others, due to the minimally pronounced sedative effect, classify this agent as the second. Be that as it may, diazolin is widely used not only in adults, but also in pediatric practice, being considered one of the most inexpensive and affordable medicines.

Desloratadine (Eden, Erius)

It is most commonly referred to as a third-generation antihistamine because it is an active metabolite of loratadine.

Cetirizine (Zodak, Cetrin, Parlazin)

Most researchers classify this drug as a second-generation antihistamine, although some confidently classify it as a third, because it is an active metabolite of hydroxyzine.

Zodak is well tolerated and rarely causes side effects. Available in the form of drops, tablets and syrup for oral administration. With a single dose of the drug, it has a therapeutic effect throughout the day, so it can be taken only 1 time per day.

Cetirizine relieves allergy symptoms, does not cause sedation, prevents the development of spasm of smooth muscles and swelling of surrounding tissues. It is effective for hay fever, allergic conjunctivitis, hives, eczema, itching is well removed.

Application features. If the drug is prescribed in large doses, then you should refrain from driving vehicles, as well as work that requires quick response. When combined with alcohol, cetirizine can enhance its negative effect.

The duration of the course of treatment with this drug can be from 1 to 6 weeks.

Fexofenadine (Telfast)

Most researchers also belong to the third generation of antihistamines, because it is an active metabolite of terfenadine. It can be used by those whose activities are related to driving vehicles, as well as those suffering from heart disease.