Pharmacological action Xyzal
Xyzal Blocker histamine H1-receptors, an enantiomer of cetirizine, is part of the competitive antagonists of histamine. Affinity for histamine H1-receptors in the levocetirizine is 2 times higher than that of cetirizine.
Levocetirizine has an impact on gistaminozavisimuyu stage of allergic reactions, and also reduces the migration of eosinophils, reduces vascular permeability, limits the release of inflammatory mediators. Prevents the development and facilitates the course of allergic reactions, has antiexudative, antipruritic effects, virtually no anticholinergic and antiserotoninovogo action. At therapeutic doses, has practically no sedation.
Effect of the drug begins 12 minutes after taking a single dose of 50% of patients after 1 h is observed in 95% and lasts for 24 hours
Pharmacokinetics Xyzal
Absorption
Pharmacokinetic parameters of levocetirizine vary linearly and do not differ from the pharmacokinetics of cetirizine. After ingestion levotsetirzin rapidly absorbed from the gastrointestinal tract. Food intake did not affect the degree of absorption, its speed decreases. After a single oral administration of a therapeutic dose Cmax in serum obtained after 0.9 h and is 207 ng / ml. Bioavailability is 100%.
Distribution
The binding of levocetirizine to plasma proteins is 90%. Vd is 0.4 L / kg.
Metabolism
Less than 14% metabolized in the liver by O-dealkylation to form a pharmacologically inactive metabolite, in contrast to other blockers of histamine H1-receptors. Not accumulates. Excreted in breast milk.
Breeding
T1 / 2 of 7-10 h. The total clearance – 0.63 ml / min / kg. Completely eliminated from the body within 96 hours 85.4% of the dose is excreted unchanged in the urine.
Farmakokinetka in special clinical situations
Patients with impaired renal function (creatinine clearance below 40 ml / min) clearance of levocetirizine is reduced, and T1 / 2 increases, which requires a corresponding change in dosing regimen. Less than 10% of levocetirizine removed during hemodialysis.
Indications Xyzal
Symptomatic treatment of allergic diseases and conditions in adults and children over 6 years:
- Perennial and seasonal allergic rhinitis and allergic conjunctivitis (itching, sneezing, rhinorrhea, lacrimation, conjunctival hyperemia);
- Hay fever (hay fever);
- Urticaria (including idiopathic urticaria);
- Angioedema;
- Allergic dermatitis, accompanied by itching and rashes.
Dosage and Xyzal
The drug is administered by mouth at meals or on an empty stomach. Tablets are taken, with some water, not chewed.
Adults and children over 6 years: 5 mg daily dose (1 tab.).
Patients with chronic renal failure with CC 49-30 ml / min the dose is reduced by 2 times (1 tab. Every other day), with CC 10.29 ml / min, reduce the dose to 3 times (1 tab. 1 every 3 days .)
Elderly patients with normal renal function, dose adjustment is required.
Patients with hepatic impairment dose adjustment is required.
Duration of treatment depends on the evidence. For the treatment of hay fever drug prescribed for an average of 1-6 weeks. In chronic diseases (perennial rhinitis, atopic dermatitis), treatment duration may be increased to 18 months.
Side effects Xyzal
CNS: headache, drowsiness, rarely – headache, dizziness.
From the digestive system: dry mouth, rarely – dyspeptic symptoms.
Other: fatigue, rare – allergic reactions (angioedema, rash, hives, itching).
Contra Xyzal
- Chronic renal failure, severe (creatinine clearance below 10 ml / min);
- Children up to age 6 years;
- Hypersensitivity to the drug;
- Hypersensitivity to piperazine derivatives.
With careful use in patients with chronic renal insufficiency of mild to moderate degree (required correction dosing regimen) in elderly patients (possibly reduced glomerular filtration rate).
Pregnancy and breast-feeding Xyzal
Drug is not recommended in pregnancy and lactation (breastfeeding).
Use in hepatic dysfunction Xyzal
Patients with hepatic impairment dose adjustment is required.
Use in renal impairment Xyzal
Patients with chronic renal failure with CC 49-30 ml / min the dose is reduced by 2 times (1 tab. Every other day), with CC 10.29 ml / min, reduce the dose to 3 times (1 tab. 1 every 3 days .)
Cautions
During the period of treatment should refrain from drinking alcohol.
Effects on ability to drive and control mechanisms
When an objective assessment of the ability to drive and operate machinery were not significantly detected no adverse effects when administered at the recommended dose of 5 mg, nevertheless advisable to refrain from activities in potentially hazardous activities that require your full attention and psychomotor speed of reaction.
Xyzal Overdose
Symptoms: possible drowsiness in children – restlessness, irritability.
Treatment: stop taking the drug to gastric lavage, activated charcoal to appoint; symptomatic therapy. No specific antidote. Hemodialysis is ineffective.
Xyzal Drug Interactions
While the use of macrolides or ketoconazole significant changes in ECG were observed.
While the use of theophylline (400 mg / day) total body clearance of levocetirizine is reduced by 16%, the pharmacokinetic parameters of theophylline did not change.
When used in therapeutic doses, no evidence of interaction with ethanol.
