Cetirizine HCl, the active ingredient in Zyrtec, is an orally active and selective H1-receptor antagonist. The chemical name is (±) - [2- [4- [ (4-chlorophenyl)phenylmethyl] -1- piperazinyl] ethoxy]acetic acid, dihydrochloride. Cetirizine HCl is a racemic compound with an empirical formula of
C21H25ClN2O3•2HCl. The molecular weight is 461.82.
Cetirizine HCl is a white, crystalline powder and is water soluble. Zyrtec tablets are formulated as white, film-coated, rounded-off rectangular shaped tablets for oral administration and are available in 5 and 10 mg strengths.
Inactive Ingredients:
Zyrtec syrup is a colorless to slightly yellow syrup containing cetirizine HCl at a concentration of 1 mg/ml (5 mg/5 ml) for oral administration. The pH is between 4 and 5.
Inactive Ingredients: