Anti-allergic agent – H1-histamine receptor blocker.
Mechanism of action
Cetirizine, the active ingredient of the drug, is a metabolite of hydroxyzine and has an antihistamine effect with antiallergic action. Cetirizine belongs to the group of competitive histamine antagonists and blocks H1-histamine receptors with little effect on other receptors and has almost no anticholinergic and antiserotonin action.
Cetirizine affects the histamine-dependent stage of immediate allergic reactions and also reduces the migration of eosinophils and limits the release of mediators in delayed-type allergic reactions. It practically does not pass through the blood-brain barrier and therefore is almost incapable of reaching central H1 receptors.
In studies of the effects of histamine on the skin, the effects of cetirizine at a dose of 10 mg began after 1 hour, peaked from the 2nd to 12th hour, and were still observed at statistically significant levels after 24 hours. In addition to its antihistamine effect, cetirizine also has an anti-inflammatory effect and thus has an effect on the late phase of the allergic reaction:
– At a dose of 10 mg once or twice daily, it inhibits the late phase of eosinophil aggregation in the skin;
– At a dose of 30 mg daily, it inhibits the release of eosinophils into the bronchial alveolar fluid after allergen-induced bronchial constriction;
– Inhibits the kallikrein-induced late inflammatory response;
– Suppresses the expression of inflammatory markers such as ICAM-1 or VCAM-1;
– Inhibits the action of histaminoliberators such as PAF or Substance P.
After oral administration, the drug is rapidly absorbed from the gastrointestinal tract. The pharmacokinetic parameters of cetirizine change linearly when administered in doses from 5 to 60 mg. The equilibrium concentration is reached after 3 days.
The pharmacokinetic profile of cetirizine is similar in adults and children. In children after taking cetirizine in a dose of 5 mg, the concentration of the active substance in the body is the same as in adults after taking 10 mg. In adults after the use of cetirizine in dose of 10 mg the maximum concentration (Cmax) in blood plasma is reached after 1-2 hours and is 350 ng/ml. In children after cetirizine administration in a dose of 5 mg, the maximum concentration (Cmax) in plasma is reached after 1 hour and is 275 ng/ml.
When cetirizine is taken in the form of drops, maximum plasma concentrations are reached at a higher rate.
Distribution after administration of 10 mg is 35 liters in adults and plasma protein binding is 93%. In children, the volume of distribution after administration of 5 mg is approximately 17 liters.
A small amount of cetirizine is excreted into breast milk.
In adults, 60% of the dose is excreted unchanged by the kidneys.
After administration of 10 mg in adults, the total clearance of cetirizine is 0.60 ml/min/kg; the half-life (T½) is approximately 10 hours. Multiple doses do not alter pharmacokinetic parameters. No cetirizine cumulation was observed when cetirizine was administered in a daily dose of 10 mg for 10 days.
After the end of treatment, plasma levels of cetirizine rapidly fall below detectable limits. Repeated allergy tests can be resumed after 3 days.
Particular patient groups
The T½ was 50% higher and the excretion rate was 40% lower in 16 elderly persons when a single dose of 10 mg of cetirizine was given compared with a control group. The decreased clearance of cetirizine in elderly patients is probably due to decreased renal function in this category of patients.
In children aged 6 to 12 years, 70% of the dose is excreted unchanged by the kidneys. After administration of 5 mg in children, the total clearance of cetirizine is 0.93 ml/min/kg.
The T½ in children from 6 to 12 years is 6 hours, from 2 to 6 years – 5 hours.
Patients with renal insufficiency:
In patients with mild renal impairment (creatinine clearance (CK) > 50 ml/min), pharmacokinetic parameters are similar to those in healthy volunteers with normal renal function.
In patients with moderate renal impairment (CK 30-49 mL/min), T½ is prolonged 3-fold and total clearance is reduced by 70% relative to healthy volunteers with normal renal function.
In patients on hemodialysis (CK < 7 ml/min), oral cetirizine doses of 10 mg decrease total clearance by approximately 70% relative to healthy volunteers with normal renal function, and T½ is prolonged by a factor of 3.
Less than 10% of cetirizine is removed by standard hemodialysis procedures.
Patients with hepatic insufficiency:
In patients with chronic liver disease (hepatocellular, cholestatic, and biliary cirrhosis), a single dose of 10 or 20 mg of cetirizine increases T½ by about 50% and decreases clearance by 40% compared with healthy subjects.
Dose adjustment is necessary only if a patient with hepatic impairment also has concomitant renal impairment.
Allergies, Allergic conjunctivitis, Pollinosis, Conjunctivitis, Neurodermatitis, Urticaria, Diathesis, Runny nose (rhinitis), Dermatitis, Skin itching, Allergic rhinitis, Dermatosis, Increased tear production
The drug is indicated in adults and children from 6 years to relieve:
– nasal and ocular symptoms of year-round (persistent) and seasonal (intermittent) allergic rhinitis and allergic conjunctivitis, such as itching, sneezing, nasal congestion, rhinorrhea, lacrimation, conjunctival hyperemia;
– symptoms of chronic idiopathic urticaria.
One tablet contains:
Cetirizine dihydrochloride – 10.0 mg;
Lactose monohydrate, 70.0 mg;
Microcrystalline cellulose, 34.0 mg;
Crospovidone, 3.6 mg;
Magnesium stearate – 1.2 mg;
Colloidal silicon dioxide – 1.2 mg;
[hypromellose – 2.40 mg, talc – 0.80 mg, titanium dioxide – 0.44 mg, macrogol 4000 (polyethylene glycol 4000) – 0.36 mg] or [dry film coating mixture containing hypromellose (60%), talc (20%), titanium dioxide (11%), macrogol 4000 (polyethylene glycol 4000) (9%)] – 4.0 mg.
How to take, the dosage
Orally, regardless of meals, without chewing and drinking plenty of fluid, preferably in the evening.
Adults and children over 6 years of age (with body weight over 30 kg) – 1 tablet once a day.
Co-administration with theophylline (400 mg/day) leads to decreased total clearance of cetirizine (the kinetics of theophylline does not change).
Myelotoxic drugs increase manifestations of hematoxicity of the drug.
No clinically significant interactions with other drugs (pseudoephedrine cimetidine ketoconazole erythromycin azithromycin diazepam glipizide) were found.
It is not recommended to use simultaneously with alcohol and medicines depressing the central nervous system.
Circular biconvex film-coated tablets, white or almost white.
On the cross section the core is white or almost white.
– hypersensitivity to cetirizine, hydroxyzine or other piperazine derivatives or any other drug components;
– moderate, severe and terminal stages of renal failure (creatinine clearance < 50 ml/min) (for this dosage form);
– childhood under 6 years of age (for this dosage form);
– hereditary lactose intolerance, lactase deficiency, glucose-galactose malabsorption syndrome.
– elderly patients (with age-related decrease in glomerular filtration);
p> – epilepsy and patients with increased seizure readiness;
-patients with predisposing factors to urinary retention (see section “Special Precautions.
– concomitant use with alcohol (see section “Interaction with other medicinal products”);
– period of breastfeeding.
The drug is usually well tolerated. Side effects are rare and transient.
Digestive system disorders: dry mouth dyspepsia.
Nervous system disorders: dizziness headache drowsiness fatigue agitation migraine.
Allergic reactions: angioedema skin rash itching urticaria.
The symptoms observed after an apparent overdose of cetirizine affected the central nervous system or were associated with possible anticholinergic effects.
The symptoms observed after taking at least five times the recommended daily dose included the following: confusion, diarrhea, fatigue, headache, malaise, mydriasis, itching, restlessness, sedation, somnolence, stupor, tachycardia, tremor, urinary retention.
There is no specific antidote. In case of overdose, symptomatic or supportive treatment is recommended. Gastric lavage and/or administration of activated charcoal may be effective if the overdose is recent. Cetirizine is partially excreted by dialysis.
The data on the use of cetirizine during pregnancy are limited (300 to 1000 pregnancy outcomes). However, no cases of malformations, embryonic or neonatal toxicity with a clear causal relationship have been identified.
The experimental studies on animals did not reveal any direct or indirect adverse effects of cetirizine on the developing fetus (including in the postnatal period), the course of pregnancy and labor.
In pregnancy, cetirizine may be administered after consultation with a physician if the anticipated benefit to the mother exceeds the potential risk to the fetus.
Cetirizine should not be used during breastfeeding because cetirizine is excreted with the breast milk in an amount from 25% to 90% of the plasma concentration, depending on the time of sampling after taking the drug. Adverse reactions associated with cetirizine may be observed in infants.
In the period of breastfeeding, use after consultation with a physician if the anticipated benefit to the mother exceeds the potential risk to the baby.
The available data on effects on human fertility are limited, but negative effects on fertility have not been identified in animal studies.
Consult your doctor before using the drug if you are pregnant, or if you think you might be pregnant, or are planning a pregnancy.
Zyrtec, Cetrine, Zodac, Cetirizine, Cetirizine-Teva, Cetirizine drops, Solonex
3 years. Do not use after the expiration date.
|Conditions of storage|
Store in a light-protected place at a temperature not exceeding 25 ºC. Store out of the reach of children.
Buy Cetirizine-Vertex, 10 mg 30 pcs with delivery to USA, UK, Europe and over 120 other countries.