Alergolik (levocetirizine) oral drops solution 5 mg/ml. 10 ml. vial №1

The pharmacokinetic parameters of levocetirizine are linear and almost do not differ from those of cetirizine.

Absorption. The drug after oral administration is rapidly and intensively absorbed. The degree of absorption of the drug does not depend on the dose of the drug and does not change with food intake, but the maximum concentration (C _max ) of the drug decreases and reaches its maximum value later. Bioavailability reaches 100%.

In 50% of patients, the effect of the drug develops 12 minutes after taking a single dose, and in 95% – after 0.5-1 hour. C _max in blood serum is reached 50 minutes after a single oral dose of a therapeutic dose. The equilibrium concentration in the blood is reached after 2 days of taking the drug. C _max is 270 ng / ml after a single application and 308 ng / ml – after repeated use at a dose of 5 mg, respectively.

Distribution. There is no information on the distribution of the drug in human tissues, as well as on the penetration of levocetirizine through the blood-brain barrier. In animal tests, the highest concentrations were found in the liver and kidneys, and the lowest in the tissues of the central nervous system (CNS). The volume of distribution is 0.4 l / kg. Plasma protein binding – 90%.

Biotransformation. In the human body, about 14% of levocetirizine is subject to metabolism. The metabolic process includes oxidation, N- and O-dealkylation, and association with taurine. Dealkylation primarily occurs with the participation of cytochrome CYP 3A4, while numerous and (or) indefinite CYP isoforms are involved in the oxidation process. Levocetirizine does not affect the activity of cytochrome isoenzymes 1A2, 2C9, 2C19, 2D6, 2E1, 3A4 at concentrations that significantly exceed the maximum after taking a dose of 5 mg orally. Given the low degree of metabolism and the lack of ability to inhibit metabolism, the interaction of levocetirizine with other substances (and vice versa) is unlikely.

Withdrawal. Excretion of the drug occurs mainly due to glomerular filtration and active tubular secretion. The half-life of the drug from blood plasma in adults (T _1/2 ) is 7.9 + 1.9 hours. The half-life of the drug is shorter in young children. The total clearance in adults is 0.63 ml / min / kg. Basically, the excretion of levocetirizine and its metabolites from the body occurs with urine (an average of 85.4% of the applied dose of the drug is excreted). With feces, only 12.9% of the applied dose of the drug is excreted.

The total clearance of levocetirizine in the body correlates with creatinine clearance. Therefore, in patients with moderate to severe renal impairment, it is recommended to select the intervals between doses of levocetirizine, taking into account creatinine clearance. With anuria in end-stage kidney disease, total clearance is reduced by approximately 80% compared with total clearance in individuals without such disorders. The amount of levocetirizine excreted during a standard 4-hour hemodialysis session was < 10%.