Due to the increase in the frequency of seasonal allergic reactions, the demand for antiallergic drugs has also increased. Until recently, second-generation antihistamines have been widely used. Compared with the previous group of medicines, these drugs have some additional properties. In particular, they are effective in hay fever, bronchial asthma, dermatitis (atopic). However, they act only on peripheral H1 histamine receptors. Many of them also have a cardiotoxic effect.
Recently, third-generation antihistamines have been used more frequently. The drugs used before them only reduced the symptoms, without in any way affecting the sensitizing activity of allergens. In other words, with severe allergic reactions, their clinical effectiveness is low.
Modern medicines (latest generation antihistamines) are selective, do not pass through the blood-brain barrier. In this regard, these drugs do not have side effects associated with the activity of the central nervous system, and also do not havedetrimental effect on cardiac function. Among the additional properties of drugs that have significant clinical significance, one should highlight the ability of drugs to reduce the phenomena of hyperreactivity of the bronchial system, the severity of bronchospasm (allergen-induced).
Latest generation antihistamines are more appropriate for long-term therapy of various manifestations of seasonal allergies, in the nature of which mediators of late stages of inflammation are of no small importance. These include, in particular, prolonged rhinitis that can manifest itself throughout the year, seasonal rhinitis, conjunctivitis, the duration of which is more than two weeks, chronic urticaria, dermatitis (atopic, contact allergic), as well as early atopic manifestations characteristic of children.
In the treatment of rhinitis, the most popular antihistamines of the latest generation, such as Acelastin, Loratadin, Cetirizine.
Drugs "Cetirizine", "Zyrtec" are also used for mild bronchial asthma. With the development of early atopic syndrome in young patients, these medications are considered essential. These latest generation antihistamines reduce the likelihood of later progression of atopic manifestations.
Medications "Claritin", "Loratadin" do not have a sedative effect. They also do not differ in significant clinical significance of drug interactions. These antihistamines are allowed to prescribepatients of different ages.
Medications also differ in their pharmacokinetic properties. The most modern drugs are characterized by a long duration of action (up to two days). As a rule, they are taken once a day. It should be borne in mind that some third-generation antihistamines (for example, Astemizol and Terfenadine) have a pronounced cardiotoxic effect, causing disruptions in the heart rhythm.
