title: Pharmacokinetics of beta-carotene and canthaxanthin after ingestion of individual and combined doses by human subjects.
abstract: OBJECTIVE
  This study investigated effects of ingestion of a combined dose of beta-carotene and canthaxanthin on their individual pharmacokinetics in serum.
  
  
  METHODS
  During three 5-day study periods, two subjects ingested either a 25 mg dose of beta-carotene, a 25 mg dose of canthaxanthin, or a combined dose of 25 mg each of beta-carotene and canthaxanthin. Pharmacokinetics of the individual and combined doses were compared within subjects.
  
  
  RESULTS
  Ingestion of a concurrent beta-carotene dose reduced the peak serum canthaxanthin concentration by 38.8 +/- 6.5%, and the 24- and 72-hour areas under the serum canthaxanthin concentration-time curves by 38.1 +/- 6.4 and 34.4 +/- 7.4%, respectively. The suggested antagonism between beta-carotene and canthaxanthin was not reciprocal; beta-carotene inhibited the appearance of canthaxanthin in serum but canthaxanthin did not inhibit the appearance of beta-carotene.
  
  
  CONCLUSIONS
  Our data suggest that ingestion of a combined pharmacologic dose of beta-carotene and canthaxanthin reduces the bioavailability of the canthaxanthin dose.
authors.affiliation: Division of Nutritional Sciences, University of Illinois, Urbana-Champaign.
authors.forename: W S
authors.initials: WS
authors.lastname: White
authors.forename: M
authors.initials: M
authors.lastname: Stacewicz-Sapuntzakis
authors.forename: J W
authors.initials: JW
authors.lastname: Erdman
authors.forename: P E
authors.initials: PE
authors.lastname: Bowen
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001682:Biological Availability; D016644:Canthaxanthin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D002338:Carotenoids / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D018592:Cross-Over Studies; D004347:Drug Interactions; D005260:Female; D006801:Humans; D008875:Middle Aged; D013997:Time Factors; D019207:beta Carotene
chemical_list: D019207:beta Carotene; D002338:Carotenoids; D016644:Canthaxanthin