The pharmacokinetic profile of ketoprofen suppositories following single and chronic (32 doses) administration to 12 healthy adult male volunteers was established. Each subject received a single rectal dose of 100 mg of ketoprofen on day 1, followed by one suppository of 100 mg b.i.d. for days 8--22, and finally one suppository on day 23. Plasma samples were analysed by gas-liquid chromatography. Following single doses, the mean maximum observed concentrations of ketoprofen in plasma (6.56 microgram ml-1) were achieved at 1.1 h; the mean elimination half-life was 1.78 h. The results indicate that ketoprofen is rapidly and reproducibly absorbed and eliminated from the suppository dose form.