Antihistamines new generation
Medicine / / August 12, 2017
- principle of action of antihistamines
- drugs against allergies new generation: features
- Modern means of allergies
Allergic diseases are among the most common human disease states.In the conditions of modern life is marked permanent increase in the frequency and severity of this type of pathology.Although allergic diseases and symptoms are not life threatening, they significantly influence the quality, so you need an adequate, effective and safe therapeutic intervention, an important component of which is the appointment of antihistamines.
principle of action of antihistamines
allergy symptoms caused by the biological effects of histamine - biogenic compounds synthesized in mast cells and basophils in their immunoglobulin-mediated activation in response to an allergen.Free histamine has high activity and binding to histamine H 1 receptors causes dilation of capillaries, increased permeability of their walls, nerve irritation, mucus secretion, and a number of other effects.This
antihistamines to treat allergies based on their ability to competitively block the H1-histamine receptors in various tissues, while leveling the biological effects of histamine.Screening of histamine H1 receptors, antihistamines for allergies can deal with the symptoms of allergic diseases.As a competitive antagonist of the first type histamine receptors, antihistamines are associated only with the free receptor, which is why their intake should be started early in the disease, when their action is most effective.
now known three generations of drugs used to relieve allergy symptoms.Maximum efficiency and minimum side effects of antihistamines have a third generation.
drugs against allergies new generation: features
main advantage of drug allergy the third generation is the lack of cardiotoxic and sedative effects characteristic of assets belonging to the first and second generations.Medicines for the new generation of allergy have a selective effect on peripheral H1 histamine receptors, they do not penetrate the blood-brain barrier, so do not have negative side effects from the CNS.Drugs in this group have additional clinically significant effects, and therefore can be used for long-term therapy of allergic diseases.Modern
antihistamines have a higher activity and a prolonged therapeutic effect (duration up to 48 hours allows to take tablets 1 - 2 times a day, avoiding multiple dose).The effectiveness of modern allergy is proved in the treatment of the following diseases:
- chronic urticaria, atopic dermatitis and other pruritic dermatoses number;
- perennial and seasonal allergic rhinitis;
- seasonal and perennial allergic conjunctivitis;
- early atopic syndrome in children;
- pseudoallergy reaction.
Modern means of allergies
most promising Antihistamines taken orally, are considered analogues and derivatives of loratadine and cetirizine.
Claritin (loratadine) - a drug long-acting antihistamine activity which lasts 24 hours.Therapeutic effect reaches through means 8 - 12 hours after ingestion.The drug is prescribed for the treatment of allergic rhinitis and conjunctivitis, urticaria, angioedema, food allergy, mild asthma.
active drug based on the primary metabolite of loratadine - erius (desloratadine) not only effectively blocks H1 histamine receptors, but also a number of mediators responsible for allergic inflammation of the system, providing antiallergic and anti-inflammatory effect within 30 minutes after administration.Means no sedative effect and has no effect on the cardiovascular system.
Zyrtec (cetirizine) - an antihistamine, a well-proven as an antipruritic and anti-inflammatory agent.The efficacy of the drug in the treatment of mild asthma, so it can be used in young children when drug delivery by inhalation path is difficult.
effectively limits the release of inflammatory mediators drug ksizal active substance is levocetirizine, the pharmacological activity of which is almost twice higher than that of cetirizine.
highly effective antihistamine is a new generation of Telfast (fexofenadine), are well-established in the treatment of seasonal allergic rhinitis and idiopathic urticaria.The drug is not metabolized in the liver and has no cumulative effect.
widespread use at present, along with oral agents, drugs for allergy found topical action.
Such funds have only a local effect, which significantly reduces the risk of unwanted side effects.
Because when applied topically in the blood concentration of the substance is significantly below that which can cause systemic effects, the frequency of respective side effects is greatly reduced.From this group of drugs widely used in medical practice and azelastine levocabastine found in the form of nasal sprays and eye drops.
nose drops levocabastine (livostin, tizin) in allergic rhinitis effectively reduce rhinorrhea, sneezing, itching in the nose, helps eliminate swelling of nasal mucosa, thereby facilitates nasal breathing.The same drug in the form of eye drops reduces the symptoms of allergic conjunctivitis (itching, redness and swelling of the eyelids, tearing, chemosis).This modern antiallergic agent begins to act a few minutes after application.Similar effects have eye drops and nasal spray azelastine (allergodil).
younger children for the treatment of allergic rhinitis prescribe topical agents such as drugs kromoglitsievoy acid (kromogeksal, kromoglin) and combination drug vibrotsil.