Classification of antihistamines. Antihistamines are the best medicines of all generations. What are antihistamines

Vasoconstrictor sprays and drops have a symptomatic effect. They reduce swelling of the mucous membrane and restore breathing.

However, these drugs have many side effects (see Vasoconstrictor drugs from the group of adrenomimetics). Therefore, it is recommended to use them only occasionally.

Local antihistamines as the only treatment are rarely used. However, they are sometimes used in the complex therapy of allergic rhinitis.

Glucocorticoid hormones are able to interrupt allergic reactions at the earliest stages. They are used most often, especially in the treatment of moderate to severe allergic rhinitis. These drugs have a lot of side effects and contraindications, so they are used only as directed by a doctor. The effect of glucocorticoids usually becomes noticeable within a few days of starting treatment.

Remember, self-medication is life-threatening, consult a doctor for advice on the use of any medications.

Currently, there are the following methods of conservative treatment of AR:

1. patient education
2. prevention of contact with allergens;
3. drug therapy;
4. specific immunotherapy;
5. surgery.

Treatment of AR aims not only to eliminate acute, severe symptoms and allergic inflammatory reactions with hypersensitivity, but also to change the patient's immune status. These goals are met by causal therapy, which provides for either the complete elimination of resolving factors or a persistent inhibition of the body's readiness for allergic reactions.

Treatment of APR should be complex and stepwise. Therapeutic options for AR are presented in the table.

It is necessary to carry out the following elimination measures:

1. Elimination (elimination of contact with the allergen)
2. Immunological (use of SIT)
3. pharmacotherapeutic (use of a wide range of drugs).
4. Patient education (learning behavioral skills to reduce the severity of response to allergens).
5. Surgical (mainly minimally invasive surgical interventions aimed at restoring nasal breathing and eliminating foci of chronic infection).

The task of therapeutic measures is to ensure that the impact of AR on the quality of life and the patient's performance is as minimal as possible.

Before starting treatment, it is necessary to clarify the form of the disease (mild, moderate, severe), as well as the episodic occurrence of symptoms. These terms are defined in the WHO program Aria (2001).

1. The definition of "mild form" means that the patient has only minor clinical signs of the disease that do not interfere with daily activities or sleep. The patient is aware of the presence of the manifestation of the disease.
2. The definition of "moderate form" means that the symptoms disturb the patient's sleep, interfere with work, study, and sports. The quality of life is significantly reduced.
3. The term "severe" means that the symptoms are so severe that the patient cannot work, study, play sports or leisure activities during the day and sleep at night unless treated. (Allergic rhinitis and impact on asthma (ARIA). WHO initiave, 2001)

Allergen prevention

The most effective causative therapy for AR is allergen elimination:

1. Elimination of allergens reduces the severity of AR, sometimes leading to the disappearance of symptoms.
2. The effect of elimination can be fully manifested only after weeks and months.
3. In most cases, the complete elimination of patient contact with allergens is impossible.
4. Elimination of allergens should be carried out before or in conjunction with drug treatment.

Measures to prevent contact with allergens

1. Pollen allergens.

More to be indoors during the flowering of plants. Close the windows in the apartment, wear safety glasses, roll up the windows and use the protective filter in the car's air conditioner while driving outside the city. Try to leave your permanent place of residence in another climatic zone (for example, take a vacation) during the flowering season. Avoiding contact with pollen is often impossible due to its high penetrating power.

2. House dust allergens.

Use sheet protectors. Replace down pillows and mattresses, as well as wool blankets with synthetic ones, wash them every week at 60°C. Get rid of carpets, thick curtains, soft toys (especially in the bedroom), do wet cleaning at least once a week, and use a washing vacuum cleaner with disposable bags and filters or vacuum cleaners with a water tank, pay special attention to cleaning upholstered furniture. It is desirable that the patient does not carry out the cleaning himself. Install air purifiers in the apartment

3. Pet allergens

If possible, get rid of pets, do not start new ones. Animals should never be in the bedroom. Wash animals regularly

The only effective measure to eliminate animal hair allergens is to remove animals (cats, dogs) from the home and thoroughly clean carpets, mattresses and upholstered furniture. However, even these measures are not enough to completely eliminate cat allergens. Although frequent bathing of cats reduces the amount of allergens in the wash water, clinical studies have not shown a beneficial effect of this procedure if it is done once a week. If the removal of a cat is unacceptable to the patient, the animal should at least be kept outside the bedroom or outside the home.

Medical treatment

In the pharmacotherapy of AR, 5 main groups of drugs are used, and the place of each of these groups is quite clearly defined by their mechanism of action on certain moments of pathogenesis or symptoms of the disease.

1. Antihistamines.
2. Corticosteroids.
3. Mast cell stabilizers.
4. Vasoconstrictor drugs.
5. Anticholinergics.

Oral and topical antihistamines:

All modern antihistamines have an effect on H1 - histamine receptors - they do not directly destroy histamine, but prevent its connection with H1 - histamine receptors, thereby eliminating the effect of histamine on target organs.

Currently, antihistamines are used in the treatment of AR, which are divided into 3 generations.

Antihistamines of the 1st generation appeared in the early 40s of the XX century, some of them are still used today:

1. Dimedrol.
2. Tavegil.
3. Diprazine.
4. Pipolfen.
5. Suprastin.
6. Diazolin (mebihydrolin)

For drugs of the 1st generation, a competitive blockade is characteristic, a reversible connection with H1 - receptors. Therefore, to achieve a clinical effect, drugs should be taken up to 3-4 times a day or high doses should be used.

The low efficiency of these drugs causes their effect on other types of receptors, which is accompanied by a number of additional undesirable effects:

1. Dryness of the mucous membranes of the mouth, nose, throat, urination disorder, disturbance of accommodation (blockade of M-cholinergic receptors).
2. Depression.
3. Quinidine-like action on the heart muscle - ventricular tachycardia.
4. Local anesthetic action.
5. analgesic effect and potentiation of analgesics.
6. Antiemetic action.
7. Due to lipophilicity, they penetrate the central nervous system, causing a range of side effects (sedation, impaired coordination, dizziness, weakness, lethargy, distraction).
8. Disorders of the gastrointestinal tract (increased appetite, nausea, diarrhea, discomfort in the epigastric region).
9. The development of tachyphylaxis - tolerance with prolonged use, with a decrease in their therapeutic effect.
10. Allergic reactions when used for more than 10 days.

Oral antihistamines are widely used in the treatment of AR.

Their mechanism of action is due to the fact that they, having a structure similar to the structure of histamine, compete with it and block H1 receptors. At the same time, the released histamine is unable to bind to a sufficient number of H1 receptors.

H1 antihistamines are divided into three generations.

1st generation (drugs with a sedative effect): diphenhydramine (diphenhydramine) tab 50 mg, 1% solution - 1 ml, suprastin (chlorpyramine) - tab. 25 mg., 2% solution - 1 ml. , tavegil (clemastine) - tab. 1 mg. , solution 0.1% (2 mg) - 2 ml., pipolfen (promethazine) dragee 25 mg. , solution 2.5% - 1 ml, Fenkarol (hifenadine) - tab. 25 mg, diazolin (mebhydrolin) tab., dragee 50-100 mg.

In addition to the blockade of H1 receptors, these drugs have a high ability to block cholinergic receptors, alpha-adrenergic receptors, and also easily penetrate the blood-brain barrier. In addition, incomplete binding to H1 receptors (~ 30%), short duration of therapeutic action (1.5 - 3 hours), tachyphylaxis (addiction on day 7), potentiation of the sedative effect of alcohol and central nervous system depressants are noted. In this connection, the following side effects are caused:

1. Drowsiness, feeling tired or agitated, sleep disturbance, anxiety, psychosis, impaired coordination of movement, concentration.
2. Dizziness, headache, low blood pressure, increased heart rate.
3. Dryness of the mucous membranes, skin, dilated pupils, blurred vision.
4. Stomach pain, constipation, nausea, vomiting, appetite stimulation, urinary retention.
5. Deterioration of the drainage function of the bronchi.
6. Increase in body weight.

Adverse events include the need to constantly change drugs due to tachyphylaxis, as well as the need to frequently increase the dose of the drug to achieve the desired stable therapeutic effect, thereby increasing the frequency and severity of side effects.

On this basis, contraindications to their use were developed:

1. Work that requires mental and motor activity, attention, concentration.
2. With astheno-vegetative syndrome
3. Bronchial asthma
4. Glaucoma
5. Peptic ulcer of the stomach and duodenum, intestinal atony
6. prostate adenoma, urinary retention
7. Taking sedatives, sleeping pills, MAO inhibitors
8. Cardiovascular diseases
9. Risk of weight gain
10. Pregnancy, feeding
11. children's age up to 1 year.

Currently, antihistamines of the 2nd and 3rd generations are mainly used in AR. However, some 1st generation antihistamines, not inferior to the latter in activity to block H1 receptors, have their own advantages:

• lower cost and availability for a wide range of patients
• the ability to use in people with sleep disorders and increased excitability 2nd generation. The 2nd generation drugs were developed in 1981. They have the following benefits:
• high specificity and affinity for H1 receptors
• rapid onset of action
• Long lasting effect - up to 24 hours
• the possibility of using high doses sufficient to relieve patients of day and night symptoms
• lack of blockade of other types of receptors, especially M-cholinergic
• no transport across the blood-brain barrier - no sedative effects
• no effect of food on absorption
• lack of tachyphylaxis with long-term use.

Preparations:

1. Terfenadine (seldan, trexil). The first non-selective antihistamine. May cause ventricular arrhythmias. Currently banned in many countries.
2. Astemizol (gismanal). In some patients, they stimulate appetite and cause weight gain. Cases of cardiac arrhythmias have been described.
3. Loratadin (claritin, loratadin-KMP, lorastin, rhinorol, agistam, lorano), 10 mg tablets of 10 and 30 per package, 1 mg / ml syrup - 120 ml in a vial. It is the drug most studied and most used in AR since 1993.
   In addition to the antihistamine action, it has a membrane-stabilizing effect, inhibits eosinophil chemotaxis, platelet aggregation, reduces vascular permeability, thereby causing the ability to reduce swelling of the nasal mucosa (decongestive effect), and reduce the sensitivity of the bronchi to histamine.
   Claritin does not cause tachyphylaxis, which makes it possible to carry out long-term prophylactic therapy as long as necessary. A long course of admission is possible if necessary - up to 1 year. Possible side effects at the placebo level. Contraindications - individual intolerance. Dosages: 1 time per day at any time, regardless of food intake. Adults and children over 12 years old - 10 mg (1 tablet or 10 ml of syrup), children from 2 to 12 years old - 5 mg (1/2 tab. Or 5 ml of syrup), children from 1 year to 2 years old - 2.5 mg (1/4 tab. or 2.5 ml of syrup).
4. Cetirizine (Cetrin, Zyrtec, Allertec).
   Cetrin - tablets of 10 mg. An effective fast acting product. The action comes in 20 minutes and lasts 24 hours. Easy to use - 1 time per day, regardless of the meal. It has a pronounced antipruritic effect. Does not cause drowsiness, does not have a cardiotoxic effect. It has a bronchodilatory effect, which is important for patients with AR in combination with bronchial asthma.
5. Acrivastine (semprex). The effect of the drug is observed after 30 minutes. After taking the average dose. The maximum effect, which coincides with the maximum concentration of the drug in plasma, occurs after 1.5-2 hours, the effectiveness lasts up to 12 hours. Dosage: adults and children over 12 years old, 1 caps. (8 mg) 3 times a day.
6. Ebastin (Kestin).
7. hifenadine (fencarol). The mechanism of the antiallergic action of phencarol is explained not only by its ability to block H1 receptors and thereby prevent the action of histamine on them, but also to activate diaminooxidase (histaminase), which leads to a decrease in the content of histamine in tissues.
8. Ketotifen (zaditen) tablet 1 mg, syrup 0.2 mg/ml. Effective in the treatment of AR and BA. The drug is safe and effective for children even three months of age.
   Dosage: adults 1 tab. (1 mg) 2 r / d with food. Children from 6 months to 3 years - 0.05 mg per 1 kg of body weight twice a day with meals. Over 3 years of age: 1 mg twice daily with food. No addiction, possible side effects: sedation, dry mouth, dizziness, weight gain.

For antihistamines 3rd generation include fexofenadine and desloratadine.

Fexofenadine(telfast, fexofast, altiva) is an active metabolite of the second-generation antihistamine drug terfenadine. Registered in 1996 for the treatment of AR, a dose of 120 mg 1 time per day is used. Has advantages:

• high selectivity of blockade of H1-histamine receptors
• fast absorption, no influence of food during the absorption stage
• valid in 30 minutes. After administration, reaches the maximum concentration in the blood after 1-2 hours, the duration of action is 24 hours
• lack of toxicity, it does not show carcinogenic, mutagenic and teratogenic effects
• characterized by a wide therapeutic index (the ratio of therapeutic and toxic doses of more than 30)
• does not penetrate the BBB, does not cause adverse reactions from the central nervous system, does not have a sedative effect
• does not require dose adjustment either in chronic liver failure or in renal failure, since an increase in its concentration in the blood under these conditions (up to two to three times) does not reach a toxic level
• does not require dose adjustment in the elderly
• does not affect the electrophysiology of the heart
• does not cause a decrease in efficiency due to tachyphylaxis
• it is possible to use together with other medicines (antibiotics, antifungals, heart remedies)

Telfast is the only antihistamine drug officially approved for use by pilots and air traffic controllers in the US, UK, Australia and Brazil.

The drug is contraindicated:

1. during pregnancy and lactation
2. in children up to 12 years of age

Desloratadine(Erius) Schering-Plough, USA - a biologically active metabolite of the second-generation antihistamine loratadine. Registered in 2000.

It has not only high selectivity and affinity for H1-histamine receptors, but also inhibits the production of the most important cytokines, chemokines and cellular activity, which determines its anti-allergic and anti-inflammatory properties. Today it demonstrates the highest selective antagonism for H1-receptors of histamine (50-200 times higher than that of lroatadine, cetirizine, fexofenadine).

Erius provides a decongestant effect in AR and reduces the severity of bronchial obstruction in bronchial asthma.

It does not affect the central nervous system, does not have a sedative effect and a negative effect on the work of the heart, and does not cause psychological disorders. Available in tablets of 5 mg and in syrup 0.5 mg / ml. The long-term therapeutic effect and high safety of Erius allows you to prescribe it once a day, regardless of food intake at any time: adults and children from 12 years old - 5 mg (1 tablet), children from 6-11 years old - 2.5 mg (5 ml of syrup), children 2-5 years old 1.25 mg (2.5 ml of syrup). Erius is the first choice in the treatment of AR with oral antihistamines.

Local antihistamines

Currently, there are 2 local antihistamines - azelastine (allergodil) and levocabastine. They are effective and highly selective H1-histamine receptor blockers. Azelastine and levocabastine nasal spray quickly relieve itching and sneezing. The drugs have a high safety profile.

Allergodil (nasal spray) Acta Medica, 10 ml bottle and dispenser. Has shown reliable efficacy in the treatment of SAD and CAR. The action occurs after 15 minutes and lasts 12 hours. Can be used until symptoms disappear, but not more than 6 months in a row. Dosage: adults and children over 6 years old - one spray in each half of the nose twice a day. Does not have systemic side effects. Side effects: sometimes irritation of the nasal mucosa. In isolated cases, nosebleeds are observed.

Local (topical) glucocorticosteroids (GCs)

The use of topical glucocorticosteroids (GCS) in AR is justified by the fact that they affect the pathogenetic links in the development of the pathological process. Corticosteroids, having a pronounced anti-inflammatory effect, reduce the release of cytokines and chemokines, reduce the number of antigen-presenting cells, T cells, eosinophils and mast cells in the mucous membrane of the nasal cavity and paranasal sinuses. In addition, corticosteroids reduce mucosal gland secretion, plasma and cell extravasation, and tissue edema. They also reduce the sensitivity of the receptors of the nasal mucosa to histamine and mechanical stimuli, that is, to a certain extent, they also affect nonspecific nasal hyperreactivity.

Currently, a number of topical corticosteroids are used for the treatment of AR, which are the most effective antiallergic drugs:

1. Beclamethasone dipropionate (Aldecin, Beconase, Nasobek).
2. Fluticosone propionate (Flixonase).
3. Mometasone furate (Nasonex).
4. Avamys (Fluticasone furoate).

beclomethasone included by WHO in the Consensus on the treatment of bronchial asthma (1993) and allergic rhinitis (1984) in adults and children (WHO guidelines "Diagnosis and treatment of AR and its impact on asthma" (ARIA) 2000)

Aldecin is a dosed glucocorticoid in an aerosol can, containing 200 doses of 50 mcg of beclomethasone dipropionate. The daily dose of Aldecin is 400 mcg per day - for adults and children over 6 years old, 2 doses in each half of the nose 2 times a day.

Baconase - nasal spray, contains 200 doses of 50 mcg. The daily dose is 200 mcg 2 times a day. Baconase is used only in adults over 18 years of age. Not used for more than 3 months.

Side effects:

1. In rare cases, perforation of the nasal septum.
2. Dryness and irritation of the mucous membrane of the nasal cavity and pharynx, unpleasant taste and smell, rarely - nosebleeds.
3. There are reports of increased intracranial pressure, the appearance of glaucoma.
4. Cases of hyperreactivity reactions are described, which manifested themselves in the form of urticaria, itching, redness and swelling of the eyes, face, lips and pharynx.

Nasobek - intranasal spray (water suspension) contains 200 doses of 50 mcg. Daily dose of 200 mg - adults and children from 12 years of age, 2 doses (100 mg) in each half of the nose 2 times a day. The drug nasobek is effective in most cases in SAD.

Side effects. There is dryness and irritation of the mucous membrane of the nose and throat, as well as blood crusts in the nose. Rarely unpleasant olfactory and gustatory perceptions.

Contraindications: hemorrhagic diathesis, frequent nosebleeds, fungal diseases, pulmonary tuberculosis, children under 12 years of age.

Flixonase - aqueous suspension fluticosone propionate containing 120 doses of 50 mcg. Daily dose of 200 mg - adults and children over 12 years old, 100 mg (2 doses) in each half of the nose 1 time per day, preferably in the morning. In some cases, it is required to apply 100 mcg (2 doses) in each half of the nose 2 times a day. The maximum daily dose should not exceed 400 mcg (4 doses) in each half of the nose. Children aged 4-11 years - 50 mg (1 dose) in each half of the nose 1 time per day. The maximum daily dose of the drug is 200 mcg (2 doses) in each half of the nose. No systemic effects were found with topical application of the drug. The drug does not give an immediate effect and the therapeutic effect appears after 3-4 days of treatment.

Side effects: in rare cases, it causes dryness and irritation of the mucous membranes of the nose and throat, unpleasant taste sensations, and nosebleeds.

Nasonex ( mometasone furoate) 0.1% - aqueous nasal metered spray. Contains 120 standard doses of 50 mcg. Nasonex has the most pronounced anti-inflammatory effect among all corticosteroids, influencing the early and late phases of the allergic inflammatory response.

The drug acts quickly, the effect appears after 7-12 hours, which distinguishes it from other inhaled corticosteroids. Nasonex has excellent tolerability and the highest safety (bioavailability less than 0.1%), which leads to the absence of a systemic effect even with a 20-fold increase in dose. High safety allows the drug to be used in children from 2 years of age.

An important advantage of Nasonex is also local safety. The drug not only does not cause atrophy of the nasal mucosa, which is characteristic of local corticosteroids, but also helps to restore the ciliated epithelium.

Nasonex is the only intranasal corticosteroid containing glycerin as a moisturizer. Dosage: adults and children over 11 years old - 2 doses (5 mcg) in each half of the nose 1 time per day. The daily dose is 200 mcg, the maintenance dose is 100 mcg per day. Children from 2 to 11 years old - 1 dorze (50 mcg) in each half of the nose 1 time per day - a daily dose of 100 mcg.

In the WHO ARIA program (2001), intranasal corticosteroid aerosols are proposed as the first choice for moderate to severe CAR and as a second line (after antihistamines) for SAD.

Indications - treatment and prevention of seasonal and year-round allergic rhinitis in adults and children from 2 years of age, as well as treatment of exacerbations of sinusitis as an auxiliary therapeutic agent along with antibiotics

It has a pronounced anti-inflammatory effect, the highest affinity for glucocorticosteroid receptors, minimal bioavailability - less than 0.1%, there is no systemic effect at all. The onset of action is already on the first day from the moment of application. applied once a day. Possible local side effects, characteristic of all topical steroids (burning in the nose, pharyngitis, headache, nosebleeds), differ slightly from placebo and less than other steroids.

Recommended doses - in the treatment of SAR and CAR: for adults and children from 12 years old - 2 inhalations in each nostril 1 time per day, after reaching the therapeutic effect, 1 inhalation. For children 2-11 years old - 1 inhalation in each nostril 1 time per day.

If necessary, the duration of the course can be up to 12 months. At the same time, the absence of a systemic and local atrophogenic effect, characteristic of other steroids, has been proven.

Cromons

For the treatment of allergic diseases, disodium cromoglycate (cromolyn) and sodium nedocromil are used. These drugs stabilize mast cell membranes, inhibit their granulation, thereby preventing the release of mediators of allergic inflammation - histamine, bradykinin, serotonin, leukotrienes and prostaglandins. The biochemical effect of cromones is associated with the blockade of intracellular penetration of calcium ions into sensitized mast cells. The drugs are less effective than antihistamines and topical GCs, but they are safe and almost completely devoid of side effects.

Cromones are not the main means of treating AR, but are indicated for the prevention and treatment of mild and moderate forms of AR.

Currently, the following cromones are widely used in the treatment of AR:

1. Cromohexal (cromoglycylic acid disodium salt) nasal spray. The drug has a local effect, when using it, less than 7.5% of the dose is absorbed from the mucous membrane and enters the systemic circulation.
   Adults and children are prescribed 1 injection in each nasal passage 4 times a day (up to 6 times if necessary). The duration of use in CAR is determined individually depending on the clinical course of the disease.
   Side effects: mild irritation of the nasal mucosa, nausea, skin rashes. Not recommended for use in the 1st trimester of pregnancy and caution when breastfeeding.
2. Ifiral (sodium cromoglycate) - 2 aqueous solution in a plastic dropper bottle. Has a local effect.
   Dosage: adults 3-4 drops in each half of the nose every 6 hours. Children over 6 years old - 1-2 drops in each half of the nose after 6 hours. The course of treatment is up to 4 weeks.
   Side effects: tingling, burning in the nasal cavity, slight irritation of the nasal mucosa, sometimes bleeding; erosive and ulcerative lesions of the nasal mucosa, sneezing; headache, taste disturbance, cough, choking, hoarseness, Quincke's edema. Contraindicated in pregnancy and lactation.
3. Cromosol (sodium cromoglycate) 2% solution for intranasal use as a metered dose aerosol in 28 ml vials (190 doses).
   Dosage. Adults and children over 6 years old - 1 injection in each half of the nose 4-6 times a day.
   Due to SAD, treatment should be started 2 weeks before flowering. With regular use, Cromosol effectively reduces the symptoms of SAD and CAR and prevents exacerbations of the disease. Reduces the need for antihistamines, reducing their unwanted side effects.
   Side effects - at the beginning of treatment, sometimes a feeling of irritation of the nasal mucosa, coughing.

Decongestants

Decongestants (D) or vasoconstrictors affect the sympathetic regulation of blood vessel tone by acting on adrenergic receptors.

They block the adrenoreceptors of the nasal mucosa, therefore they are also called adrenomimetics (or sympathomimetics), cause constriction of the blood vessels of the nasal concha, reduce their swelling.

Basically, D is applied topically, the effect comes quickly. It is used in short courses (3-10 days) before the onset of action of basic drugs, since it is possible to develop drug-induced rhinitis, increase blood pressure, especially in the elderly. In children, D is usually used for 3-5 days. They are better than other topical drugs to eliminate nasal congestion. It is desirable for young children to use short-acting drugs due to prolonged ischemia not only of the blood vessels of the nasal mucosa, but also of the cerebral vessels, which can provoke general convulsions. In children under 1 year of age, the appointment of vasoconstrictor drops should be very careful.

Distinguish:

• Alpha 1 - adrenomimetics
• Alpha2 - adrenomimetics
• Pronorepinephrine (ephedrine)
• Drugs that inhibit the utilization of norepinephrine (cocaine)

A. Non-selective alpha 2-agonists: I. Oxymetazoline Hydrochloride (Afrin, Medistar, Nazivin, Nasal Spray, Nazol, Rinazoline, Fervex Spray, Oxymetazoline Hydrochloride) II. Xylometazoline (galazolin, nasal, Dr. Theis, ximelin, xylometazoline, otrivine, rizxin, farmazolin). III. Naphazoline (naphthyzine). B. Selective alpha 2-agonists: I. Naphazoline nitrate (sanarin). II. Tetrizoline hydrochloride (tizine) III. Tramazoline hydrochloride (lazolnasal plus) IV. Phenylephrine (Vibrocil, Polydex, Nazol Baby, Nazol Kids)

• Combined preparations: contains a local adrenoblocker, antihistamines and other drugs (rinofluimucil, sanarin-analergin, vibrocil, knock-spray, Dr. Theis, polydex)
• Oral decongestants: - pseudoephedrine (actifed, trifed, clarinase)
• phenylephrines (orinol plus).

Oxymetazoline hydrochloride

1. Afrin (Schering-Plough, USA) - 0.05% nasal spray, 20 ml in a vial. It has a fast, pronounced vasoconstrictor effect, provides a long-lasting effect.

Method of application and dosage: adults and children over 6 years old, 2-3 injections in each half of the nose 2 times a day.

2. Nazivin (Merck KGa A) - 0.01%, 0.025%, 0.05% solution of 5-10 ml in a vial.

Method of application and dosage: infants under the age of 4 weeks, 1 cap. 0.01% solution in each nasal passage 2-3 times a day. From 5 weeks of life to 1 year, 1-2 drops in each nasal passage 2-3 times a day.

Children from 1 to 6 years of age: 0.05% solution, 1-2 drops in each nasal passage 2-3 times a day.

Adults and children over 6 years old: 0.05% solution, 1-2 caps. in each nasal passage 2-3 times a day. Should be applied for 3-5 days. Does not have a systemic effect.

Side effects: sometimes burning or dryness of the nasal membranes, sneezing. Abuse of Nazivin can cause atrophy of the mucous membrane and reactive hyperemia, drug-induced rhinitis, damages the epithelium of the mucous membrane.

3. Nazol (Sagmel) - 0.05% nasal spray, 15-30 ml in a vial.

Dosage and administration: adults and children over 12 years of age, 2-4 injections in each nasal passage 2 times a day.

Children from 6 to 12 years old: 1 injection every 12 hours. Should not be used more than 2 times a day. It is not recommended to use more than 3 days.

Contraindications: angle-closure glaucoma, arterial hypertension, vascular atherosclerosis, cardiac arrhythmias, diabetes mellitus, thyrotoxicosis, impaired renal function, atrophic rhinitis, children under 6 years of age.

4. Rinazolin (Farmak) - 0.01%, 0.025%, 0.05% solution of 10 ml in a vial. The action is manifested 15 minutes after taking the drug, the duration of action is 10-12 hours.

For infants during the first 4 weeks of life, instill 1 drop of 0.01% solution 2 times a day into each nasal passage. Starting from 5 weeks until the end of the 1st year of life, 1-2 drops 2 times a day.

Children from 1 to 6 years old - 0.025% solution 1-2 drops in each nasal passage 2 times a day.

Adults and children over 6 years: 1-2 drops. 0.05% solution in each nasal passage 2 r / day. The course of treatment is 3-5 days (in some cases up to 7-10 days)

Side effects: symptoms of irritation of the nasal mucosa - dryness, burning sensation of the nasal mucosa, sneezing. Rarely observed nausea, agitation, tachycardia, increased blood pressure, sleep disturbance.

Xylometazoline

1. Galazolin (Warsaw FZ) - 0.05% or 0.1% solution, 10 ml in a vial.

Dosage and administration: children from 2 to 12 years old are administered 2-3 caps. 0.05% solution in each nasal passage every 8-10 hours.

Adults and children over 12 years of age are injected with 2-3 drops of 0.1% solution in both halves of the nose every 8-10 hours. The course of treatment is 3-5 days. Do not use for more than 2 weeks, as this can lead to the development of secondary drug-induced rhinitis. Side effects: burning sensation or tingling in the nasal cavity, dryness of the nasal mucosa.

2. For the Nose (Novartis) - 0.05% solution, 10 ml in a dropper bottle, 0.1% spray, 10 ml in a bottle, is practically not absorbed when applied topically.

Dosage and administration: adults and children over 6 years of age use 1 injection in each half of the nose, no more than 4 times a day.

0.05% solution: for children over 6 years old - 2-3 drops in both halves of the nose, 3-4 times a day. Infants and up to 6 years - 1-2 drops in each half of the nose 1-2 times a day.

Side effects: with frequent or prolonged use - dryness of the mucous membrane of the nasopharynx, burning, tingling in the nasal cavity, sneezing, hypersecretion.

3. Otrivin (Novartis) - 0.05% and 0.1% solution in a 10 ml vial.

when applied topically, the drug is practically not absorbed, does not disrupt the function of the ciliated epithelium of the nasal mucosa.

Dosage and administration:

0.05% solution for infants (from 3 months of age) and children under 6 years old, 1-2 drops in each half of the nose 1-2 times a day. No more than 3 times a day.

0.1% solution: adults and children over 6 years old, 2-3 drops in each half of the nose, up to 4 times a day. The duration of the drug - no more than 3 days.

Contraindications: Do not use in patients with transsphenoidal hypophysectomy or dural exposure surgery.

4. Farmazolin (Farmak) - 0.05% and 0.1% solutions in 10 ml vials.

The action of the drug begins 5-10 minutes after the introduction into the nasal cavity, lasts 5-6 hours.

Dosage and administration: adults and children over 12 years old: 103 drops of 0.05% or 0.1% solution in each half of the nose 103 times a day.

Children from 6 months to 5 years, 1-2 drops, children under 6 months, 1 drop 1-3 times a day. The course of treatment is 3-5 days.

Contraindications: angle-closure glaucoma, atrophic rhinitis, arterial hypertension, hyperthyroidism, tachycardia, severe atherosclerosis.

Nafazoline

Naphthyzine (Belmedpreparaty) - 0.05% and 0.1% solutions, 10 ml each in a vial.

Causes prolonged constriction of blood vessels. It is not recommended to use it for a long time, as its therapeutic effect gradually decreases.

Dosage and administration: 0.1% solution for adults and children, 2-3 drops in both halves of the nose 2-3 times a day.

0.05% solution for children over 1 year old, 1-2 drops in both halves of the nose 2-3 times a day

children under 1 year of age are not prescribed the drug.

Contraindications: arterial hypertension, tachycardia, severe atherosclerosis.

B. Selective alpha 2-agonists

I. Naphazoline nitrate

1. Sanorin (Galena) - emulsion for intranasal use in a 10 ml vial.

has vasoconstrictive and anti-inflammatory action. Differs in fast, expressed and long action.

Dosage and administration:

Adults: 1-3 drops of the emulsion in each half of the nose 2-3 times a day.

Contraindications: age up to 2 years, arterial hypertension, thyroid hyperplasia, tachycardia, severe atherosclerosis.

Side effects: irritation of the mucous membrane, with prolonged use - swelling of the mucous membrane, nausea, headache, increased blood pressure, tachycardia.

II. Tetrizoline hydrochloride

1. Tizin (Pfizer) - 0.05% and 0.1% solutions in 10 ml vials.

The action of the drug begins 1 minute after application and lasts for 4-8 hours.

Dosage and administration: 0.1% solution for adults and children over 6 years old, 2-4 drops in each half of the nose 3-4 times a day. 0.05% solution for children from 2 to 6 years old, 2-3 drops in each half of the nose 3-4 times a day.

Tizin should not be used for more than 3-5 days.

Side effects: reactive hyperemia, burning sensation of the mucous membrane, general reaction (tachycardia, headache, tremor, weakness, sweating, increased blood pressure) are sometimes observed.

III. Tramazoline hydrochloride

1. Lazolnazal Plus (Boehringer Ingelheim) - spray in a 10 ml vial.

It contains the sympathomimetic tramazolin hydrochloride, which has a vasoconstrictor effect, and essential oils (eucalyptus, camphor and mint), moisturizing the mucous membrane, which helps to avoid dryness in the nose. After nasal injection, the action occurs within a few minutes and lasts 8-10 hours.

Dosage and administration: adults and children over 6 years old, 1 injection in each half of the nose 3-4 times a day.

Use the drug for no more than 5-7 days.

IV. Phenylephrine is a selective alpha 2-agonist.

Reduces edema by increasing the outflow of blood from the vessels of the nasal cavity, without disturbing the active circulation in the mucous membrane. The effect occurs 5 minutes after the introduction of the drug into the nasal cavity.

1. Vibrocil (Novartis) - a combined drug with vasoconstrictor and antiallergic action, contains phenylephrine and dimethidine maleate, adapted for children.

Phenylephrine is a sympathomimetic that selectively stimulates alpha-adrenergic receptors of cavernous venous vessels of the nasal mucosa, has a moderate vasoconstrictive effect.

Dimetindene is a histamine H1 receptor antagonist.

Available in the form of drops, spray and gel.

Nose drops - 15 ml in a bottle with a dropper cap. Dosage and administration: children under 1 year - 1 drop; children from 1 to 6 years old - 1-2 drops, children over 6 years old and adults 3-4 drops. The drug is instilled into each half of the nose 3-4 times a day.

Nasal spray - 10 ml. Children over the age of 6 years and adults are prescribed 1-2 injections in each half of the nose 3-4 times a day.

Nasal gel - 12 g in a tube. For children over the age of 6 years and adults, the gel is injected into each half of the nose 3-4 times a day.

Vibrocil should not be used for more than 2 weeks. Longer or excessive use causes tachyphylaxis, mucosal edema (“rebound” phenomena) or drug-induced rhinitis.

Anticholinergics

Ipratropium bromide is a muscarinic receptor antagonist. It inhibits the development of local rhinorrhea, which develops with the participation of cholinergic mechanisms. In this regard, ipratropium bromide reduces only rhinorrhea. Nasal congestion, itching, and sneezing are common in patients with AR, so other drugs are preferred in the vast majority of these patients.

Allergen-Specific Immunotherapy (ASI)

In 1907, A. Bezredko proved that the state of hypersensitivity (allergy) can be significantly reduced if increasing doses of the causative allergen are consistently administered. This discovery continued to be used in modern allergology, conducting specific immune therapy (SIT).

At present, the effectiveness of SIT has been confirmed in a large number of controlled studies both abroad and in our country. ASI is indicated for patients with clinical signs of an IgE-mediated disease and should be started early in the course of allergic disease for maximum benefit. ASI should be carried out by an allergist.

INDICATIONS FOR SIT

• Allergic rhinitis (rhinoconjunctivitis)
• Mild and moderate form of bronchial asthma, with indicators of more than 70% of FEV1 due values ​​after adequate therapy
• Patients whose symptoms are not adequately controlled after allergen elimination and pharmacotherapy
• Patients with both bronchial and rhinoconjunctival symptoms
• insect allergy
• Patients who refuse long-term use of pharmacological drugs
• Patients in whom pharmacotherapy produces undesirable side effects

CONTRAINDICATIONS TO SIT

• Severe immunopathological conditions and immunodeficiencies
• Oncological diseases
• Severe mental disorders
• Treatment with beta-blockers, including topical forms
• Inability to comply with the prescribed treatment regimen
• Severe form of bronchial asthma, uncontrolled by pharmacotherapy (less than 70% after adequate therapy)
• Cardiovascular diseases that can cause complications with the use of adrenaline (epinephrine)
• Children under 5 years old
• Delayed positive skin tests with antigen (immunoglobulins are predominantly class E as antibodies)
• Acute infections
• Somatic diseases with dysfunction of organs and systems
• Complicated course of AR

Relative contraindications are:

• Age 50 and over
• Skin diseases
• chronic infectious diseases
• Mild skin tests with allergens
• Inefficiency of the previous SIT (if any)

The duration of SIT is determined by the allergist. Usually, the maximum effect develops 1-2 years after its onset, although the elimination or significant reduction in allergy manifestations can be observed already after 1-3 months. The optimal period for conducting SIT is considered to be 3-5 years, and if it does not give an effect within a year, it is stopped.

In recent years, along with parenteral methods of SIT, non-invasive methods of administering allergy vaccines (sublingual, oral, intranasal) have been successfully used.

Currently, oral SMIT is widely used in Ukraine (by means of dragees with allergens). The relative high efficiency of oral SIT is due to two two points of contact of the allergen with immunocompetent cells: in the region of the lymphopharyngeal ring and in the Peyer's patches of the intestine, where part of the allergen enters with swallowed saliva. The advantages of SIT by the method of using dragees with allergens should be attributed (D.I. Zabolotny et al., 2004):

1. High efficiency (over 80% of excellent and good results);
2. Less frequency of adverse reactions;
3. Rapid achievement of maintenance dose (11 days);
4. Less need for supervision by health workers (possibility of use in rural areas);
5. Convenience for healthcare workers and patients;
6. Greater aesthetics of the method, the absence of discomfort, which reduces the number of failures from SIT;
7. The best possibility of combining with pharmacotherapy;
8. Higher economy.

According to the consensus opinion on the treatment of AR (Allergy, 2000; 55), stepwise regimens for the treatment of SAD and CAR are recommended.

(C) V.V. Bogdanov, A.G. Balabantsev, T.A. Krylova, M.M. Kobitsky "Allergic rhinitis (etiology, pathogenesis, clinic, diagnosis, treatment, prevention)"
Guidelines (for students, interns, graduate students, undergraduates, clinical residents, family doctors, general practitioners, otorhinolaryngologists, allergists, therapists, pediatricians).
Simferopol - 2005
UDC 616.211.-002-056.3
A 50
Approved by the Academic Council of the Faculty of Dentistry of the Crimean State Medical University. S.I. Georgievsky (protocol No. 4 dated November 17, 2005).

There are several classifications of antihistamines (histamine H1 receptor blockers), although none of them is considered generally accepted. According to one of the most popular classifications, antihistamines are divided into I and II generation drugs according to the time of creation. First-generation drugs are also commonly called sedatives (according to the dominant side effect), in contrast to second-generation non-sedative drugs.

Currently, it is customary to isolate the third generation of antihistamines. It includes fundamentally new drugs - active metabolites, which, in addition to high antihistamine activity, are characterized by the absence of a sedative effect and the cardiotoxic effect characteristic of second-generation drugs.

Most of the antihistamines used have specific pharmacological properties, which characterizes them as a separate group. These include the following effects: antipruritic, decongestant, antispastic, anticholinergic, antiserotonin, sedative and local anesthetic, as well as the prevention of histamine-induced bronchospasm.

Antihistamines are histamine H1 receptor antagonists, and their affinity for these receptors is much lower than that of histamine (Table No. 1). That is why these drugs are not able to displace the histamine associated with the receptor, they only block unoccupied or released receptors.

Table number 1. Comparative efficacy of antihistamine drugs in terms of the degree of blockade of histamine H1 receptors

Accordingly, blockers H 1 Histamine receptors are most effective in preventing immediate allergic reactions, and in the case of a developed reaction, they prevent the release of new portions of histamine. The binding of antihistamines to receptors is reversible, and the number of blocked receptors is directly proportional to the concentration of the drug at the location of the receptor.

Stimulation of H 1 receptors in humans leads to an increase in smooth muscle tone, vascular permeability, itching, slowing of atrioventricular conduction, tachycardia, activation of the branches of the vagus nerve that innervates the respiratory tract, an increase in cGMP levels, an increase in the formation of prostaglandins, etc. In tab. No. 2 showing localization H 1 receptors and the effects of histamine mediated through them.

Table number 2. Localization H 1 receptors and the effects of histamine mediated through them

Table No. 3 AGP classification

First generation antihistamines.

All of them are well soluble in fats and, in addition to H1-histamine, also block cholinergic, muscarinic and serotonin receptors. Being competitive blockers, they reversibly bind to H1 receptors, which leads to the use of rather high doses.

The most characteristic pharmacological properties of the first generation are:

• · Sedative action is determined by the fact that most of the first generation antihistamines, being easily dissolved in lipids, penetrate the blood-brain barrier well and bind to the H1 receptors of the brain. Perhaps their sedative effect consists of blocking the central serotonin and acetylcholine receptors. The degree of manifestation of the sedative effect of the first generation varies in different drugs and in different patients from moderate to severe and increases when combined with alcohol and psychotropic drugs. Some of them are used as sleeping pills (doxylamine). Rarely, instead of sedation, psychomotor agitation occurs (more often in medium therapeutic doses in children and in high toxic doses in adults). Due to the sedative effect, most drugs should not be used during tasks that require attention. All first-generation drugs potentiate the action of sedative and hypnotic drugs, narcotic and non-narcotic analgesics, monoamine oxidase inhibitors and alcohol.
• The anxiolytic effect characteristic of hydroxyzine may be due to the suppression of activity in certain areas of the subcortical region of the central nervous system.
• Atropine-like reactions associated with the anticholinergic properties of drugs are most characteristic of ethanolamines and ethylenediamines. Manifested by dry mouth and nasopharynx, urinary retention, constipation, tachycardia and visual impairment. These properties ensure the effectiveness of the discussed remedies in non-allergic rhinitis. At the same time, they can increase obstruction in bronchial asthma (due to an increase in sputum viscosity, which is not desirable for people suffering from bronchial asthma), exacerbate glaucoma and lead to infravesical obstruction in prostate adenoma, etc.
• · Antiemetic and antiswaying effects are also likely to be associated with the central anticholinergic action of the drugs. Some antihistamines (diphenhydramine, promethazine, cyclizine, meclizine) reduce the stimulation of vestibular receptors and inhibit the function of the labyrinth, and therefore can be used for motion sickness.
• · A number of H1-histamine blockers reduce the symptoms of parkinsonism, which is due to the central inhibition of the effects of acetylcholine.
• · Antitussive action is most characteristic of diphenhydramine, it is realized through a direct action on the cough center in the medulla oblongata.
• The antiserotonin effect, which is primarily characteristic of cyproheptadine, determines its use in migraine.
• · The alpha1-blocking effect with peripheral vasodilation, especially seen with phenothiazine antihistamines, may lead to a transient decrease in blood pressure in sensitive individuals.
• Local anesthetic (cocaine-like) action is characteristic of most antihistamines (occurs due to a decrease in membrane permeability to sodium ions). Diphenhydramine and promethazine are stronger local anesthetics than novocaine. However, they have systemic quinidine-like effects, manifested by prolongation of the refractory phase and the development of ventricular tachycardia.
• · Tachyphylaxis: decrease in antihistamine activity with long-term use, confirming the need for alternating drugs every 2-3 weeks.

It should be noted that the first generation antihistamines differ from the second generation in the short duration of exposure with a relatively rapid onset of the clinical effect. Many of them are available in parenteral forms.

All of the above, low cost, insufficient public awareness about the latest generations of antihistamines determine the widespread use of first generation antihistamines today.

The most commonly used are chloropyramine, diphenhydramine, clemastine, cyproheptadine, promethazine, phencarol, and hydroxyzine.

Table No. 4. Preparations of the 1st generation:

Second generation antihistamines

Unlike the previous generation, they have almost no sedative and anticholinergic effects, but differ in their selective action on H1 receptors. However, for them, a cardiotoxic effect was noted to varying degrees (Ebastin (Kestin)).

The most common properties for them are the following:

• High specificity and high affinity for H1 receptors with no effect on choline and serotonin receptors.
• Rapid onset of clinical effect and duration of action. Prolongation can be achieved due to high protein binding, accumulation of the drug and its metabolites in the body, and delayed elimination.
• Minimal sedation when using drugs in therapeutic doses. It is explained by the weak passage of the blood-brain barrier due to the peculiarities of the structure of these funds. Some particularly sensitive individuals may experience moderate drowsiness.
• Lack of tachyphylaxis with prolonged use.
• · Absence of parenteral formulations, however, some of them (azelastine, levocabastine, bamipine) are available as topical formulations.
• 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.

In this case, the use of antihistamines of the 1st and 2nd generations is not desirable for people with cardiovascular pathologies. A strict diet is required.

The benefits of second generation antihistamines are as follows:

• · Due to their lipophobicity and poor penetration through the blood-brain barrier, second-generation drugs have practically no sedative effect, although it can be observed in some patients.
• The duration of action is up to 24 hours, so most of these drugs are prescribed once a day.
• · Lack of addiction, which makes possible the appointment for a long time (from 3 to 12 months).
• After discontinuation of the drug, the therapeutic effect may last for a week.

Table No. 5. Preparations of the II generation of antihistamines

Antihistamines III generation.

Drugs of this generation are prodrugs, that is, pharmacological active metabolites are quickly formed in the body from the original form, which have a metabolic effect.

If the parent compound, unlike its metabolites, had undesirable effects, then the occurrence of conditions under which its concentration in the body increased could lead to serious consequences. This is exactly what happened at the time with the drugs terfenadine and astemizole. Of the H1 receptor antagonists known at that time, only cetirizine was not a prodrug, but a drug in itself. It is the final pharmacologically active metabolite of the first generation drug hydroxyzine. Using the example of cetirizine, it was shown that a slight metabolic modification of the original molecule makes it possible to obtain a qualitatively new pharmacological drug. A similar approach was used to obtain a new antihistamine fexofenadine based on the final pharmacologically active metabolite of terfenadine. Thus, the fundamental difference between III generation antihistamines is that they are active metabolites of antihistamines of the previous generation. Their main feature is the inability to influence the QT interval. Currently, third-generation drugs are represented by cetirizine and fexofenadine. These drugs do not cross the blood-brain barrier and therefore do not cause side effects from the central nervous system. In addition, modern antihistamines have some significant additional anti-allergic effects: they reduce the severity of allergen-induced bronchospasm, reduce the effects of bronchial hyperreactivity, and there is no feeling of drowsiness.

III generation drugs can be taken by persons whose work is associated with precise mechanisms, transport drivers.

Table No. 6. Comparative characteristics of antihistamines

Allergy is considered an epidemic of the XXI century. Antihistamines are widely used to prevent and relieve allergy attacks.

In 1936, the first drugs appeared. Antihistamines have been known for more than 70 years, but already have a fairly large range: from I to III generations. The effectiveness of antihistamines of the first generation in the treatment of allergic diseases has long been established. Although all of these drugs quickly (usually within 15-30 minutes) alleviate allergy symptoms, most of them have a pronounced sedative effect and can cause unwanted reactions at recommended doses, as well as interact with other drugs. Antihistamines of the first generation are used primarily for the relief of acute allergic reactions.

The advantages of second-generation antihistamines include a wider range of indications for use. The action of the drug develops rather slowly (within 4-8 weeks), and the pharmacodynamic effects of second-generation drugs have been proven only predominantly in vitro.

Recently, third-generation antihistamines have been created that have significant selectivity and do not have side effects from the central nervous system. The use of third-generation antihistamines is more justified in the long-term treatment of allergic diseases.

The pharmacokinetic properties of antihistamines vary considerably. Modern third-generation antihistamines have a longer duration of action (12-48 hours).

However, this is not the end, the study of antihistamines continues to this day.

allergic disease antihistamine

Dear friends, I greet you!

Acrivastine (Semprex) and terfenadine also belonged here, but they caused severe cardiac arrhythmias, even death, so they disappeared from the shelves.

pros:

1. High selectivity for H1 receptors.
2. They do not have a sedative effect.
3. They operate for a long time.
4. Side effects when taking them are noted much less frequently.
5. They are not addictive, so they can be used for a long time.

Minuses:

Safe at recommended dosages. Passing through the liver, they are metabolized by it. But if the functions are impaired, non-metabolized forms of the active substance accumulate in the blood, which can cause heart rhythm disturbances. You have probably seen that some of the annotations mention the QT interval. This is a special section of the electrocardiogram, the lengthening of which indicates the likelihood of ventricular fibrillation and sudden death.

In this regard, patients with impaired liver and kidney function need to change the dose.

3rd generation antihistamines

This group of drugs includes desloratadine ( Erius, Lordestin, Desal, etc.), levocetirizine ( Xizal, Suprastinex and others), fexofenadine ( Allegra, Feksadin, Fexofast, etc.).

These are active metabolites of second generation drugs, so their metabolic products do not accumulate in the blood, causing heart problems, and do not interact with other drugs, causing side effects.

Pros:

• Outperforms their predecessors in performance.
• They act quickly and for a long time.
• They do not have a sedative effect.
• Do not slow down the reaction rate.
• Do not enhance the effect of alcohol.
• They are not addictive, so they can be used for a long time.
• They do not have a toxic effect on the heart muscle.
• There is no need to change the dose in patients with impaired liver and kidney function.
• The safest.

I didn't find any cons in general.

Here you go. The preparatory work is done, you can move on to the preparations.

First of all, let's sketch out what might be of interest to an allergy sufferer who asks you for an antiallergic drug.

He wants the drug:

• Was efficient.
• Started to act quickly.
• Taken once a day.
• Didn't cause drowsiness.
• Did not reduce the reaction rate (for motor transport drivers).
• Was compatible with alcohol.

And you and I, as always, are still interested in nursing, children and the elderly.

This is how we will analyze the active substances using the example of the most popular over-the-counter drugs.

1 generation.

Suprastin tablets

• Begins to act in 15-30 minutes, the action lasts 3-6 hours.
• shown with any allergic reactions, except for bronchial asthma. In general, antihistamines are not the main drugs for asthma. They are weak for asthmatics. If they are used, then only in combination with bronchodilators. And the first generation does cause dryness of the mucous membranes, making it difficult to expectorate.
• Causes drowsiness.
• Pregnant, lactating is contraindicated.
• Children - from 3 years (for this form).
• A lot of side effects.
• It is better not to recommend for the elderly.
• Drivers can't.
• The effect of alcohol enhances.

Tavegiltablets

Everything is the same as suprastin, only it lasts longer (10-12 hours), so it is taken less often.

Other differences:

• The sedative effect is less compared to Suprastin, but the therapeutic effect is also weaker.
• Children - from 6 years old (for this form).

Diazolintablets, dragees

• It begins to act in 15-30 minutes, the action can last for an incomprehensible amount. They write that even up to 2 days. Then the question is the frequency of reception.
• Children from 3 years old. Up to 12 years - a single dose of 50 mg, then - 100 mg.
• May cause irritability in children.
• Pregnant, lactating women are not allowed.
• Not recommended for the elderly.
• Drivers can't.

Fenkaroltablets

• It penetrates poorly through the BBB, so the sedative effect is negligible.
• Starts working in an hour.
• From 3 to 12 years old - 10 mg tablets, from 12 years old - 25 mg, from 18 years old - 50 mg.
• In pregnancy - weigh the risk / benefit, contraindicated in the 1st trimester.
• Nursing is not allowed.
• Side effects are much less than those discussed above.
• Drivers of vehicles beware.

2 generation

Claritin (loratadine) tablets, syrup

• Begins to act 30 minutes after ingestion.
• The action lasts 24 hours.
• Does not cause drowsiness.
• Does not cause arrhythmias.
• Indications: hay fever, urticaria, allergic dermatitis.
• Lactation is not allowed.
• Pregnancy - with caution.
• Children - syrup from 2 years old, tablets from 3 years old.
• Does not enhance the effect of alcohol.
• Drivers can.

I noticed that the instructions for generics indicate that it is contraindicated during pregnancy. Why, then, is there a “loophole” for Claritin in the form of a vague “with caution”?

Zyrtec (cetirizine ) - tablets, drops for oral administration

• Begins to act within an hour, the effect lasts 24 hours.
• Does not have a sedative effect (in therapeutic doses).
• Indications: urticaria, dermatitis, Quincke's edema.
• Effective for cold allergies.
• The greatest effect was shown in the treatment skin allergies.
• Children - drops from 6 months, tablets - from 6 years.
• Refrain from alcohol.
• Drivers, be careful.

Kestin (ebastine)- coated tablets 10 mg, 20 mg and lyophilized 20 mg

• The effect of the film-coated tablets begins after 1 hour and lasts 48 hours ( record holder!).
• After 5 days of admission, the effect persists for 72 hours.
• Indications: hay fever, urticaria, other allergic reactions.
• Pregnancy, lactation - contraindicated.
• Children: from 12 years old.
• Drivers can.
• Hearts - with caution.
• 20 mg film-coated tablets - recommend if lower dosage fails.
• 20 mg lyophilized tablets dissolve instantly in the mouth: for those who find it difficult to swallow.

Fenistil (dimetindene) drops, gel

• Drops - the maximum concentration in the blood after 2 hours.
• Indications: hay fever, allergic dermatoses.
• Drops for children - from 1 month. Caution up to 1 year to avoid apnea (stop breathing) against the background of a sedative effect.
• Pregnancy - except for the 1st trimester.
• Nursing is not allowed.
• Contraindicated - bronchial asthma, prostate adenoma, glaucoma.
• The effect of alcohol enhances.
• Drivers better not.
• Gel - for skin dermatosis, insect bites.
• Emulsion - easy to take on the road, ideal for a bite: thanks to the roll-on applicator, it can be applied pointwise.

3rd generation

Aerius (desloratadine) - tablets, syrup

• Begins to act in 30 minutes and lasts 24 hours.
• Indications: hay fever, urticaria.
• Especially effective in allergic rhinitis - eliminates nasal congestion. It has not only anti-allergic, but also anti-inflammatory effect.
• Pregnancy and lactation - contraindicated.
• Children - tablets from 12 years old, syrup from 6 months.
• Side effects are very rare.
• Drivers can.
• The effect of alcohol does not enhance.

Allegra (fexofenadine) - tab. 120, 180 mg

• Begins to act in an hour, and the action lasts 24 hours.
• Indications: allergic (tablet 120 mg), urticaria (tablet 180 mg).
• Pregnancy and lactation - contraindicated.
• Children - from 12 years old.
• Drivers, be careful.
• Seniors, be careful.
• The effect of alcohol - no indication.

Nasal and ophthalmic antihistamines

Allergodil- nasal spray.

It is used for allergic rhinitis in children from 6 years old and adults 2 times a day.

Suitable for long term use.

Allergodil eye drops - children from 4 years old and adults 2 times a day for allergic.

Sanorin-analergin

It is used from the age of 16 for allergic rhinitis. It is good because it contains vasoconstrictor and antihistamine components, i.e. acts both on the cause of allergic rhinitis and on the symptom (congestion). Begins to act in 10 minutes, and the action lasts 2-6 hours.

Pregnant and lactating is contraindicated.

Vizin Alergi- eye drops.

Contains only an antihistamine component. It is applied from 12 years, not on lenses. Not recommended for pregnant and lactating women.

That's all.

Finally, I have questions for you:

1. What other popular antihistamines have I not mentioned here? Their features, chips?
2. What questions should you ask a customer asking for an allergy remedy?
3. Have something to add? Write.

With love to you, Marina Kuznetsova

Spring. Nature is awakening… Primroses are blooming… Birch, alder, poplar, hazel let out coquettish earrings; buzzing bees, bumblebees, collecting pollen ... The season begins (from Latin pollinis pollen) or hay fever - allergic reactions to plant pollen. Summer is coming. Cereals bloom, tart wormwood, fragrant lavender ... Then autumn comes and ragweed becomes the “mistress”, the pollen of which is the most dangerous allergen. During the flowering of the weed, up to 20% of the population suffers from lacrimation, cough, allergic. And here is the long-awaited winter for allergy sufferers. But here many are waiting for a cold allergy. Spring again ... And so all year round.

And also off-season allergies to animal hair, cosmetics, house dust and more. Plus drug allergies, food. In addition, in recent years, the diagnosis of "allergy" is made more often, and the manifestations of the disease are more pronounced.

Alleviate the condition of patients with drugs that relieve the symptoms of allergic reactions, and above all - antihistamines (AHP). Histamine, which stimulates H1 receptors, can be called the main culprit of the disease. It is involved in the mechanism of occurrence of the main manifestations of allergies. Therefore, antihistamines are always prescribed as antiallergic drugs.

Antihistamines - blockers of H1 histamine receptors: properties, mechanism of action

The mediator (biologically active mediator) histamine affects:

• Skin, causing itching, hyperemia.
• Respiratory tract, causing edema, bronchospasm.
• Cardiovascular system, causing increased vascular permeability, cardiac arrhythmia, hypotension.
• Gastrointestinal tract, stimulating gastric secretion.

Antihistamines relieve symptoms caused by endogenous histamine release. They prevent the development of hyperreactivity, but do not affect either the sensitizing effect (hypersensitivity) of allergens, or the infiltration of the mucosa by eosinophils (a type of leukocyte: their content in the blood increases with allergies).

Antihistamines:

It should be borne in mind that the mediators involved in the pathogenesis (mechanism of occurrence) of allergic reactions include not only histamine. In addition to it, acetylcholine, serotonin and other substances are “guilty” of inflammatory and allergic processes. Therefore, drugs that have only antihistamine activity stop only acute manifestations of allergies. Systematic treatment requires complex desensitizing therapy.

Generations of antihistamines

According to the modern classification, there are three groups (generations) of antihistamines:
H1 histamine blockers of the first generation (tavegil, diphenhydramine, suprastin) - penetrate through a special filter - the blood-brain barrier (BBB), act on the central nervous system, exerting a sedative effect;
H1 histamine blockers II generation (fencarol, loratadine, ebastine) - do not cause sedation (in therapeutic doses);
H1 histamine blockers of the III generation (Telfast, Erius, Zyrtec) are pharmacologically active metabolites. They do not pass through the BBB, they have a minimal effect on the central nervous system, therefore they do not cause sedation.

The characteristics of the most popular antihistamines are shown in the Table:

Benefits of 3rd generation antihistamines

This group includes pharmacologically active metabolites of some drugs of previous generations:

• fexofenadine (telfast, fexofast) - an active metabolite of terfenadine;
• levocetirizine (ksizal) - a derivative of cetirizine;
• desloratadine (erius, desal) is the active metabolite of loratadine.

The latest generation of drugs is characterized by significant selectivity (selectivity), they act exclusively on peripheral H1 receptors. Hence the benefits:

1. Efficiency: rapid absorption plus high bioavailability determine the rate of removal of allergic reactions.
2. Practicality: do not affect performance; the absence of sedation plus cardiotoxicity eliminates the need for dose adjustments in elderly patients.
3. Safety: not addictive - this allows you to prescribe long courses of therapy. There is practically no interaction with concomitantly taken drugs; absorption does not depend on food intake; the active substance is excreted “as is” (unchanged), i.e., target organs (kidneys, liver) do not suffer.

Prescribe medications for seasonal and chronic rhinitis, dermatitis, allergic bronchospasm.

3rd generation antihistamines: names and dosages

note: dosages are for adults.

Feksadin, telfast, fexofast take 120-180 mg x 1 time per day. Indications: symptoms of hay fever (sneezing, itching, rhinitis), idiopathic (redness, pruritus).

Levocetirizine-teva, xyzal are taken 5 mg x 1 time per day. Indications: chronic allergic rhinitis, idiopathic urticaria.

Desloratadin-teva, Erius, Desal are taken 5 mg x 1 time per day. Indications: seasonal hay fever, chronic idiopathic urticaria.

Third generation antihistamines: side effects

With their relative safety, third-generation H1 histamine receptor blockers can cause: agitation, convulsions, dyspepsia, abdominal pain, myalgia, dry mouth, insomnia, headache, asthenic syndrome, nausea, drowsiness, dyspnea, tachycardia, visual impairment, weight gain , paronyria (unusual dreams).

Antihistamines for children

Xyzal drops are prescribed for children: over 6 years old at a daily dose of 5 mg (= 20 drops); from 2 to 6 years in a daily dose of 2.5 mg (= 10 drops), more often 1.25 mg (= 5 drops) x 2 times a day.
Levocetirizine-teva - dose for children over 6 years old: 5 mg x 1 time per day.

Erius syrup is allowed for children aged 1 to 6 years: 1.25 mg (= 2.5 ml of syrup) x 1 time per day; from 6 to 11 years: 2.5 mg (= 5 ml of syrup) x 1 time per day;
adolescents from 12 years old: 5 mg (= 10 ml of syrup) x 1 time per day.

Erius is able to inhibit the development of the first phase of an allergic reaction and inflammation. In the case of a chronic course of urticaria, the reverse development of the disease occurs. The therapeutic efficacy of Erius in the treatment of chronic urticaria was confirmed in a placebo-controlled (blinded) multicenter study. Therefore, Erius is recommended for use in children from one year old.

Important: A study of the effectiveness of Erius lozenges in the pediatric group has not been conducted. But the pharmacokinetic data revealed in the study of the determination of drug doses with the participation of pediatric patients indicate the possibility of using lozenges of 2.5 mg in the age group of 6-11 years.

Fexofenadine 10 mg is prescribed for adolescents from 12 years of age.

The doctor tells about allergy drugs and their use in pediatrics:

Prescribing antihistamines during pregnancy

During pregnancy, third-generation antihistamines are not prescribed. In exceptional cases, the use of telfast or fexofast is allowed.

Important: Information on the use of drugs of the fexofenadine (Telfast) group by pregnant women is not enough. Since studies conducted on experimental animals have not revealed signs of an adverse effect of Telfast on the overall course of pregnancy and intrauterine development, the drug is considered conditionally safe for pregnant women.

Antihistamines: from diphenhydramine to erius

Many allergy sufferers owe the first generation of antihistamines an improvement in well-being. "Side" drowsiness was taken for granted: but the nose does not flow and the eyes do not itch. Yes, the quality of life suffered, but what to do - the disease. The latest generation of antihistamines has made it possible for a large cohort of allergy sufferers not only to get rid of their allergy symptoms, but also to live a normal life: drive a car, play sports, without the risk of falling asleep on the go.

4th generation antihistamines: myths and reality

Often in the advertising of drugs for the treatment of allergies, the term “new generation antihistamine”, “fourth generation antihistamine” slips. Moreover, not only antiallergic drugs of the latest generation, but also drugs under new trademarks belonging to the second generation are often included in this non-existent group. This is nothing more than a marketing gimmick. In the official classification, only two groups of antihistamines are indicated: the first generation and the second. The third group is pharmacologically active metabolites, which have been assigned the term "H1 histamine blockers of the III generation".