Cetirizine is the active metabolite of the antihistamine agent hydroxyzine and is preferred for use in treating human skin allergies because it has less of a sedative effect than the parent compound. The authors investigate the pharmacokinetics of cetirizine in healthy cats, using high performance liquid chromatography to measure plasma levels up to 24 hours after a single 5mg dose of cetirizine dihydrochloride.
Concentrations remained above the effective human concentration for at least 24 hours after treatment.
American Journal of Veterinary Research 69 (5): 670-674.
Abstract reproduced by kind permission of Veterinary Practice magazine