Metabolism and pharmacokinetics of /sup 14/C-cetirizine in humans

Journal Article · Tue Dec 01 04:00:00 EST 1987 · Ann. Allergy; (United States)

OSTI ID:5481313

Wood, S G; John, B A; Chasseaud, L F; Yeh, J; Chung, M

This study investigated the metabolism and pharmacokinetics of cetirizine, a new H1-receptor antagonist. Single oral doses of /sup 14/C-cetirizine dihydrochloride (10 mg) in aqueous solution were administered to six healthy male volunteers. The drug was rapidly absorbed: The peak mean concentration of radioactivity (359 ng-equivalents/mL) and of unchanged drug (341 ng/mL) were achieved within one hour. Mean concentrations of cetirizine declined biexponentially and had a mean elimination half-life of 7.4 hours. The drug was excreted quite rapidly, with 60% of the dose recovered in the 24-hour urine. An additional 10% was excreted in urine over the next four days. Approximately 10% of the dose was excreted in feces over the five-day study period. The dose was excreted mainly as the unchanged drug. Examination of the radioactive compounds present in the plasma, and excreted in the urine and feces indicate that there is little metabolism of cetirizine. One minor metabolite, formed by oxidative O-dealkylation of the cetirizine side chain, was detected in plasma and feces.

• Research Organization: Huntingdon Research Centre Ltd., Cambridgeshire, England
• OSTI ID: 5481313
• Journal Information: Ann. Allergy; (United States), Journal Name: Ann. Allergy; (United States) Vol. 59; ISSN ANAEA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
AZOLES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL HALF-LIFE
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
CARBON 14 COMPOUNDS
FECES
HETEROCYCLIC COMPOUNDS
HISTAMINE
IMIDAZOLES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MATERIALS
METABOLISM
METABOLITES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
REACTION KINETICS
TRACER TECHNIQUES
WASTES