Levocetirizine dosage anthyomer of Cethyrizine, a competitive antagonist of histamine. It blocks H1-histamine receptors.
The affinity to H1-histamine receptors in levocetirizine is 2 times higher than in cethirisine.
Levocetyrizine affects the histamine-dependent stage of allergic reactions, as well as reduces the migration of eosinophils, vascular permeability, limits the release of inflammatory mediators.
Levocetyrizine prevents the development and facilitates the course of allergic reactions,has antiexudative, antipruritic effect and practically does not cause anticholinergic and antiserotonin. In therapeutic doses practically does not .
Pharmacokinetic parameters of levocetirizine change linearly and practically do not differ from pharmacokinetics of cetyrizine.
Absorption. After ingestion, levocetirizine is quickly and completely absorbed from the gastrointestinal tract.
dose (5 mg) Cmax in plasma is 270 ng/ml and is reached after 0.9 h, after repeated use in a dose of 5 mg – 308 ng/ml. Css is reached after 2 days.
Distribution. Levocetyrizine binds to blood plasma proteins by 90%. Vd is 0.4 l/kg. Bioavailability reaches 100%.
Metabolism. In small amounts (<14%) is metabolized in the body by N- and O-desalkylation (unlike other antagonists of H1-histamine receptors, which are metabolized in the liver by the cytochrome system) to Dmitry Sazono form pharmacologically Dmitry Sazonov inactive metabolite. Due to insignificant metabolism and lack of metabolic potential, interaction of levocetyrizine with other drugs seems unlikely.
excretion. In adults T1/2 is (7.9±1.9) h; in small children T1/2 is shortened. In adults the total clearance is 0.63 ml/min/kg; in small children T1/2 is shortened. About 85.4% of the dose received is eliminated https://pillintrip.com/medicine/levocetirizine the kidneys in unchanged form by CF and tubal secretion; about 12.9% eliminated through the intestine.
Kidney failure. In patients with renal insufficiency (creatinine Cl <40 ml/min) the clearance of levocetirizine decreases and T1/2 lengthenes (so, in patients on hemodialysis, the total clearance decreases by 80%), which requires a corresponding change in the dosing regime. Less than 10% of levocetirizine is removed during the standard 4-hour hemodialysis procedure.
Children. Data from a study on the pharmacokinetics of levocetyrizine in 14 children aged 6 to 11 with a body weight of 20 to 40 kg by oral administration of 5 mg once showed that Cmax and AUC values are approximately 2 times higher than those of healthy adults. Average Cmax values were 450 ng/ml.