Sunizine

Cetirizine hydrochloride.

Each tablet contains Cetirizine HCl 10mg.

Pharmacology: In experimental animals, cetirizine has been shown to be an anti-H1 agent devoid of any significant anticholinergic or antiserotonin effects. At pharmacological active doses, it induces neither sedation nor behavioural changes. This may be explained by the fact that cetirizine does not cross the blood-brain barrier.
It was shown in human pharmacology studies that cetirizine will inhibit certain effects produced by exogenous histamine. This activity appears rapidly. Cetirizine also inhibits the effects produced by endogenous histamine released in vivo by an agent eg 48/80. Finally, it inhibits the cutaneous reaction induced by VIP (Vasoactive Intestinal Polypeptide) and substance P, neuropeptides that are believed to take part in the allergic reaction.
Cetirizine markedly reduces bronchial hyper-reactivity to histamine in the asthmatic patient. It also reduces the allergic reaction induced by specific allergens. These effects are obtained without central effects being demonstrated either by psychometric test or by a quantified EEG.
Pharmacokinetics: Peak blood levels of the order of 0.3 mg/ml are reached between 30 and 60 minutes after administration of a 10 mg dose of cetirizine. Its plasma half-life is approximately 11 hours. Absorption is very consistent from one subject to the next. Its renal clearance is 30 ml/minute and the excretion half-life is approximately 9 hours. Cetirizine is strongly bound to plasma proteins.

Adults and children of 3 years or above: Symptomatic treatment of seasonal rhinitis, perennial allergic rhinitis and urticaria of allergic origin.

Oral administration.
Adult : 1 tablet (10mg) daily.
Children 6 - 12 years : 1/2 tablet (5mg) twice daily or 1 tablet (10mg) once daily.
Children 3 - 6 years : 1/2 tablet (5mg) once daily.
In patients with renal insufficiency, dosage should be reduced to ½ the daily dose. It is advisable to take the drug with a little liquid during the evening meal since the symptoms for which the product is given usually appear during the night. In patient affected by side effects, the dose may be taken as 5mg in the morning and 5mg in the evening.

Drowsiness can be a symptom of overdosage, occurring from administration of 50mg of cetirizine as a single dose.
To date, there is no specific antidote.
In the case of massive overdosage, gastric lavage should be performed as soon as possible. Usual supportive measures should be provided and routine observation carried out regularly.

Patients with a history of hypersensitivity to any constituents of the product.
Use in lactation: Cetirizine is contraindicated in lactating women since it is excreted in breast milk.

At therapeutic doses, cetirizine does not potentiate the effect of alcohol (at blood level of 0.8 g/L). Care should, however, be taken.
Activities Requiring Mental Alertness: In clinical trials the occurrence of somnolence has been reported in some patients taking cetirizine. Due caution should therefore be exercised when driving a car or operating potentially dangerous machinery. Patient should be advised, however, to take care not to exceed the recommended dose.

Use in pregnancy: Teratology studies in animals have not demonstrated any special adverse effects. As a precaution, however, cetirizine should not be administered to a pregnant woman during the first 3 months of pregnancy.
Use in lactation: Cetirizine is contraindicated in lactating women since it is excreted in breast milk.

There have been occasional reports of mild and transient subjective side effects such as headache, dizziness, drowsiness, agitation, dry mouth and gastrointestinal discomfort. In objective tests of psychomotor function, the incidence of sedation with cetirizine was similar to that of placebo. Occasionally, symptoms of hypersensitivity have been reported.

To date, there are no known interactions with other drugs. Nevertheless, cetirizine should be used with caution if sedatives are also being taken.

Store at or below 30°C. Protect from light.
Shelf-Life: 3 years.

Antihistamines & Antiallergics

R06AE07 - cetirizine ; Belongs to the class of piperazine derivatives used as systemic antihistamines.

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