title: Disposition of atovaquone in humans.
abstract: Atovaquone is an antiprotozoal compound with good in vitro stability against metabolic inactivation. Previous human studies which did not involve radiolabelling had not accounted for a substantial proportion of the dose. The possible metabolism of atovaquone in men was examined in a radiolabelling study involving four healthy male volunteers. Radioactivity was eliminated almost exclusively via the feces. All radioactivity in plasma, urine, and feces was accounted for by atovaquone, with no evidence of metabolites. Radiolabelled atovaquone was administered to a patient with an indwelling biliary tube after surgery. Biliary radioactivity was approximately 10- to 40-fold higher than that in plasma and was accounted for by atovaquone. Atovaquone is not significantly metabolized in humans but is excreted into bile against a high concentration gradient.
authors.affiliation: Department of Clinical Pharmacology, Wellcome Research Laboratories, Beckenham, Kent, United Kingdom.
authors.forename: P E
authors.initials: PE
authors.lastname: Rolan
authors.forename: A J
authors.initials: AJ
authors.lastname: Mercer
authors.forename: E
authors.initials: E
authors.lastname: Tate
authors.forename: I
authors.initials: I
authors.lastname: Benjamin
authors.forename: J
authors.initials: J
authors.lastname: Posner
mesh_terms: D000328:Adult; D000981:Antiprotozoal Agents / Q000493:pharmacokinetics*; D053626:Atovaquone; D001646:Bile / Q000378:metabolism; D001659:Biliary Tract / Q000378:metabolism; D001662:Biliary Tract Surgical Procedures; D002250:Carbon Radioisotopes; D005243:Feces; D006801:Humans; D008297:Male; D008875:Middle Aged; D009285:Naphthoquinones / Q000493:pharmacokinetics*
chemical_list: D000981:Antiprotozoal Agents; D002250:Carbon Radioisotopes; D009285:Naphthoquinones; D053626:Atovaquone