Antihistamines

Antihistamines are a pharmacological group of medicinal substances that suppress the activity of specific histamine receptors in the cells of the body. The effect of these drugs is to eliminate the spasm of smooth muscles of the intestine and bronchi, reduce the permeability of capillaries, alleviate the course of reactions of the allergic type, prevent the tissue edema.

Antihistamines are in most cases available without a prescription. Such drugs include Bromfeniramin, Chlorpheniramine, Clemastin, Dimedrol, Loratadin.

Drugs that are available only on prescription: "Cetirizine", "Desloratadine", "Focsofenadine". These drugs almost do not cause side effects, which are manifested by dry mouth or drowsiness.

Antihistamines are classified into three groups, according to their structure: ethylenediamines, ethanolamines, alkylamines, piperazines, tricyclics. The first, the second type of drugs causes a characteristic side effect - drowsiness, which somewhat limits their use. To eliminate this drawback, alkylamines have been developed. They are used to relieve the symptoms of colds: lacrimation, sneezing, cold. The purpose of using piperazines is to influence the areas of the brain responsible for the occurrence of a feeling of motion sickness, dizziness, nausea, vomiting. Antihistamines for pregnant women are tricyclics. They are used for the treatment of toxicoses, a sedative effect. All the data of a group of medicinal substances in medical practice are combined into first-generation drugs.

Today, a significant number of experiments and trials of drugs. On the basis of these two new generations of antihistamines were isolated. They differ in chemical composition and in the number of side effects. Antihistamines of the third generation operate only on target organs, do not affect other body systems. They were developed for the treatment of Alzheimer's disease.

The mechanism of action of the preparations of this pharmacological group consists in the displacement of histamine from the tissue systems, the blockage of the receptors of the glandular cells and smooth musculature. As a result, an obstacle is created for the onset of allergy symptoms . Drugs are the most effective in the case of continuous reception.

Contraindications for antihistamines are hypersensitivity to their active substances. There are undesirable effects in cases of taking and monooxidase inhibitors. Patients with glaucoma and breastfeeding mothers are also undesirable to use these medications (before the use of mandatory medical advice). Currently, antihistamines for infants have been developed, which are similar in composition to those of the third generation. They cause minimal side effects and do not affect the metabolic processes of the body.

Drugs antihistamine series are available in the form of liquid, tablets, capsules. Frequency of reception directly depends on their type and features.

Medicinal substances can not be combined with drugs that have a sedative effect, since they significantly enhance it. These drugs include tranquilizers. It is not recommended to combine antihistamines with monooxidase inhibitors, phaseline sulfate, trannicyl quipromil.

Specific side effects of substances in this group are dry mouth, drowsiness, delayed urination, loss of visual acuity.