Ondansetron absorption in adults: effect of dosage form, food, and antacids.
Ondansetron is a competitive serotonin 5-HT3 receptor blocker that has proved useful in the prevention of emesis due to cisplatin and other cancer chemotherapeutic agents. In a randomized, open-label, crossover study in 24 healthy male subjects, the relative bioavailability of a single 8-mg tablet was compared with that of an 8-mg solution using the two one-sided t-tests. The tablet and solution formulations were bioequivalent, as confirmed by similarities in mean Cmax (26.3 vs 27.7 ng/mL), Tmax (1.79 vs 1.70 h), and AUC (166.0 vs 167.3 ng.h/mL) values. In another randomized, open-label, crossover study in 12 healthy male subjects, the bioavailability of an 8-mg ondansetron tablet administered 5 min after a standard meal was slightly but significantly greater than in fasted subjects, as indicated by comparative mean AUC values [201.4 ng.h/mL (fed) vs 172.5 ng.h/mL (fasted)]. Coadministration of a magnesium hydroxide/aluminum hydroxide antacid did not affect the bioavailability of the ondansetron tablet.
Bozigian
H P
HP
Glaxo Inc., Research Triangle Park, NC 27709.
Pritchard
J F
JF
Gooding
A E
AE
Pakes
G E
GE
D000042:Absorption; D000284:Administration, Oral; D000328:Adult; D000863:Antacids / Q000494:pharmacology*; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical; D018592:Cross-Over Studies; D004347:Drug Interactions; D005215:Fasting; D005502:Food; D006801:Humans; D008297:Male; D017294:Ondansetron / Q000008:administration & dosage* / Q000493:pharmacokinetics* / Q000494:pharmacology; D012996:Solutions; D013607:Tablets
D000863:Antacids; D012996:Solutions; D013607:Tablets; D017294:Ondansetron