PHARMACOKINETICS
Cetirizine is rapidly absorbed from the gastrointestinal tract after oral administration, peak plasma concentrations being attained in about one hour. Food delays the time to peak plasma concentrations but does not decrease the amount of drug absorbed. It is highly bound to plasma proteins and has been detected in breast milk. Cetirizine is excreted primarily in the urine mainly as unchanged drug. Cetirizine does not appear to cross the blood-brain barrier to a significant extent.
INDICATIONS
Cetirizine hydrochloride is a piperazine derivative and metabolite of hydroxyzine; it is a non-sedating anti-histamine which is long-acting and has some mast-cell stabilising activity. It is used for the symptomatic relief of allergic conditions including rhinitis, and chronic urticaria.
DOSAGE AND ADMINISTRATION
In adults and children of 6 years and over, cetirizine hydrochloride is given by mouth in a dose of 10 mg once daily or 5 mg twice daily. In children aged 2 to 6 years old a dose of 5 mg once daily or 2.5 mg twice daily may be used for seasonal allergic rhinitis. In patients with renal impairment it is recommended that the dosage is reduced to half the usual daily dose. Or as prescribed by the physician
PRECAUTIONS
Drowsiness is a major problem with the sedating antihistamines and those affected should not drive or operate machinery; alcohol should be avoided. Antihistamines should not be given to neonates owing to their increased susceptibility to antimuscarinic effects.
ADVERSE REACTIONS
The most common side effect of the sedating antihistamines is CNS depression with effects varying from slight drowsiness to deep sleep but for non sedating antihistamines, they generally cause little or no drowsiness. Occasional gastrointestinal side-effects of antihistamines include nausea, vomiting, diarrhoea, or epigastric pain. Antihistamines may sometimes cause rashes and hypersensitivity reactions including bronchospasm, angioedema, and anaphylaxis and cross sensitivity to related drugs may occur. Photosensitivity can be a problem, particularly with the phenothiazine antihistamines. Other adverse effects that have been reported with the antihistamines include convulsions, sweating, myalgia, paraesthesias, extra-pyramidal effects, tremor, sleep disturbances, depression, confusion, tinnitus, hypotension, and hair loss
AVAILABILITY
Cetirizine Hydrochloride 10 mg tablet, blister pack of 10’s, box of 100’s
STORAGE CONDITION:
Store at temperatures not exceeding 30° C. |
