Loratadine, tablets 10 mg 30 pcs

Pharmacodynamics

Loratadine is a tricyclic compound with a pronounced antihistamine action and is a selective blocker of peripheral H1-histamine receptors. It has a rapid and prolonged antiallergic effect. Onset of action is within 30 minutes after ingestion. Antihistamine effect reaches a maximum after 8-12 hours from the beginning of action and lasts for more than 24 hours.

Loratadine does not penetrate through the blood-brain barrier and has no effect on the central nervous system (CNS). It has no clinically significant anticholinergic or sedative effect, i.e. does not cause drowsiness and does not affect the speed of psychomotor reactions when used in the recommended doses. Administration of loratadine does not lead to prolongation of the QT interval on the electrocardiogram (ECG).

Loratadine has no significant selectivity towards H2-histamine receptors. It does not inhibit norepinephrine reuptake and has almost no effect on the cardiovascular system or rhythm driver function.

No clinically significant changes in vital signs, physical examination data, laboratory findings or electrocardiography were observed during long-term treatment.

Pharmacokinetics

Loratadine is quickly and well absorbed in the gastrointestinal tract. Time to reach maximum concentration (Tmax) of loratadine in blood plasma is 1-1.5 hours, and its active metabolite desloratadine – 1.5-3.7 hours. Food intake increases Tmax of loratadine and desloratadine by about 1 hour, but has no effect on the effectiveness of the drug.

Maximum concentration (Cmax) of loratadine and desloratadine is independent of food intake. In patients with chronic renal disease the maximum concentration (Cmax) and the area under the curve “concentration – time” (AUC) of loratadine and its active metabolite are increased compared to patients with normal renal function.

The half-life (T½) of loratadine and its active metabolite in this case does not differ from that of healthy patients. In patients with alcoholic liver damage Cmax and AUC of loratadine and its active metabolite increased twice in comparison with these figures in patients with normal liver function, while pharmacokinetics of its active metabolite did not change significantly.

Loratadine has a high degree (97-99%) and its active metabolite – a moderate degree (73-76%) of binding to plasma proteins.

Loratadine is metabolized to desloratadine by cytochrome P450 3A4 system and, to a lesser extent, by cytochrome P450 2D6 system. It is excreted through the kidneys (about 40% of the dose taken orally) and through the intestines (about 42% of the dose taken orally) for more than 10 days, mainly as conjugated metabolites.

Approximately 27% of the ingested dose is excreted through the kidneys within 24 hours after drug administration. Less than 1% of the active substance is excreted unchanged through the kidneys within 24 hours after drug intake.

Bioavailability of loratadine and its active metabolite is dose-dependent. Pharmacokinetic profiles of loratadine and its active metabolite in adult and elderly healthy volunteers were comparable.

The half-life (T½) of loratadine is 3 to 20 hours (mean 8.4 hours) and that of desloratadine is 8.8 to 92 hours (mean 28 hours); in elderly patients, 6.7 to 37 hours (mean 18.2 hours) and 11 to 39 hours (mean 17.5 hours) respectively. The half-life (T½) increases with alcoholic liver damage (depending on the severity of the disease) and does not change with chronic renal failure.

Hemodialysis in patients with chronic renal failure has no effect on the pharmacokinetics of loratadine and its active metabolite.

Indications

Active ingredient

Composition

How to take, the dosage

Interaction

Special Instructions

Contraindications

Side effects

Overdose

Pregnancy use

Similarities