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APO-CETIRIZINE 10mg tablets are white, oval tablets deep-scored, engraved '10mg' on one side, 'APO' on the other. Each tablet contains 10mg of Cetirizine Hydrochloride and typically weighs 160mg.
Cetirizine, a human metabolite of hydroxyzine, is a histamine H1-receptor antagonistic anti-allergic compound; its principal effects are mediated via selective inhibition of peripheral activity. H1-receptors. Cetirizine hydrochloride is distinguished from other histamine H1-receptor antagonists by the presence of a carboxylic acid function. This difference may be partly responsible for the selectivity of cetirizine hydrochloride seen in pharmacologic models and it distinctive pharmacokinetic properties in humans. Cetirizine has no significant sedative or antimuscarinic activity. Cetirizine does not readily penetrate into the CNS. Cetirizine exhibits greater affinity for peripheral H1-receptors than for central H1-receptors. Cetirizine exhibits weak anticholinergic effects. There is no evidence that tolerance to the antihistaminic effects of cetirizine hydrochloride occurs or that cetirizine hydrochloride has any abuse potential or dependence liability.
Cetirizine is rapidly absorbed from the gastro-intestinal tract after oral
administration with peak plasma levels after a 10mg dose are approximately
300ng/mL and occur about one hour after dosing. The onset of activity occurs
within 20 to 60 minutes and persists for at least 24 hours following a single
dose. Bioavailability is unchanged and time to peak plasma concentrations
delayed when administered with food.
Cetirizine is approximately 93% bound to plasma proteins. The plasma elimination
half-life is approximately 8-9 hours and does not change with multiple dosing.
Pharmacokinetics are dose independent and plasma levels are proportional to the
dose administered over the clinically studied range of 5 to 20mg.
Cetirizine is less extensively metabolised than other antihistamines and
approximately 60% of an administered dose is excreted unchanged in 24 hours. The
high bioavailability associated with generally low inter-subject variation in
blood level is attributable primarily to first-pass metabolism. Only one
metabolite has been identified in humans - the product of oxidative dealkylation
of the terminal carboxymethyl group. The antihistaminic activity of this
metabolite is negligible.
Nasal symptoms associated with seasonal and perennial allergic rhinitis, such as sneezing, rhinorrhea and nasal pruritus, as well as non-nasal symptoms associated with conjunctivitis such as occular pruritus and tearing.
Symptoms and signs of in various types of pruritus and urticaria including chronic idiopathic urticaria. It significantly reduces the occurrence, severity and duration of hives.
Adults and children 6 years of age and over:
One APO-CETIRIZINE tablet once daily. In Children this can be administered in 2
divided doses of 5mg or a once daily dose of 10mg. If a sufficient response is
not obtained the dose may be increased to the maximum daily dose of 20mg.
Children 2 - 6 years of age:
Half an APO-CETIRIZINE (5mg) tablet once daily.
APO-CETIRIZINE is contraindicated in patients who have shown hypersensitivity to the drug or its components.
Do not exceed the recommended dose.
Driving/Use of Machinery
APO-CETIRIZINE is presumed to be safe or unlikely to produce an effect on the
ability to drive or use machinery. However, the individual response should be
determined before driving or performing other tasks that require alertness.
Although this medicine is unlikely to affect the ability to drive or operate machinery, a few people may be impaired and care should be taken.
Use in Pregnancy and Lactation
CATEGORY B2
The safe use of APO-CETIRIZINE during pregnancy or lactation has not been
established and therefore the compound should only be used if the potential
benefit outweighs the potential risk to the fetus or the infant. Since
APO-CETIRIZINE is excreted in breast milk and because of the increased risk of
antihistamines for infants, particularly newborns and premature infants, a
decision should be made whether to discontinue nursing or discontinue
APO-CETIRIZINE use.
Use in Children
The safety and efficacy of APO-CETIRIZINE in children younger than 2 years of
age have not been established. Long term safety and efficacy of APO-CETIRIZINE
in children between the ages of 2 and 12 have not been demonstrated. Therefore
it is desirable that APO-CETIRIZINE not be administered to children between the
ages of 2 and 12 for longer than 14 days, unless recommended by a physician.
Use in patients with Liver Impairment
Patients with severe liver impairment should be administered a lower initial
dose because they may have reduced clearance of APO-CETIRIZINE; an initial dose
of 5mg once daily or 10mg every other day is recommended.
In clinical trials the incidences of adverse effects associated with cetirizine hydrochloride have been evaluated in more than 6000 patients treated with daily doses ranging from 5 to 20mg. The most common adverse effects were somnolence (7.4%), fatigue (3.3%) and Dry mouth (2.7%). The incidence of somnolence associated with cetirizine hydrochloride was dose related and predominantly mild to moderate. Most adverse effects reported during cetirizine hydrochloride treatment were mild to moderate. There was no difference by gender or by body weight with regard to the incidence of adverse reactions. From clinical trials the following adverse effects occurred in less than 1% of those studied: Nausea, Dizziness, Insomnia, weight increase, abdominal pain, anxiety, rash, dry skin, pruritus, urticarcia and taste loss.
No clinically significant drug interactions have been found with theophylline, pseudoephedrine, cimetidine, erythromycin and ketoconazole. Epidemiologic data suggests that there also would not be interaction with other macrolide antibiotics or imidazole antifungals. In clinical trails, cetirizine hydrochloride has been safely administered with beta-agonists, non-steroidal anti-inflammatory drugs, oral contraceptives, narcotic analgesics, corticosteroids, H2-antagonists, cephalosporins, penicillins, thyroid hormones and thiazide diuretics. Interaction studies with cetirizine hydrochloride and alcohol or diazepam indicate that cetirizine hydrochloride does not increase alcohol-induced or diazepam-induced impairment of motor and mental performance.
Laboratory Test Interactions
APO-CETIRIZINE should be discontinued approximately 48 hours prior to skin
testing procedures since antihistamine may prevent or diminish otherwise
positive reactions to dermal reactivity indicators.
No reports of fatalities or life-threatening conditions have been associated with an overdose of cetirizine. Somnolence, tachycardia, rash, fatigue, urinary retention, pruritus and tremor have been reported with overdoses of 60 to 300mg of Cetirizine. There is no specific antidote to a cetirizine overdose. In the event of overdosage, treatment, which should be started immediately, is symptomatic and supportive. Discontinuation of use, gastric lavage (except in patients with impaired consciousness) and support of vital functions are advised. Cetirizine is not effectively removed by dialysis
Store below 25°C.
Protect from heat, light and moisture.
Pharmacy Only Medicine
Bottles of 100, 200 and 500 tablets.
Blister packs of 15 and 30 tablets.
Tablets contain Lactose and Cornstarch.
Apotex NZ Ltd
32 Hillside Road
Glenfield
Private Bag 102-995
North Shore Mail Centre
Auckland
Tel: (09) 444-2073
Fax: (09) 444 2951
13 March 2002