Onset and duration of analgesia for low-dose ketoprofen in the treatment of postoperative dental pain

Abstract

The objective of this single dose, double-blind study was to determine the relative analgesic efficacy of low-dose ketoprofen (6.25 mg, 12.5 mg, and 25 mg) compared with ibuprofen (200 mg) and placebo in 175 patients with moderate to severe postoperative pain secondary to extraction of impacted third molars. Analgesia was measured during the 6-hour period after administration based on onset of relief, hourly and summary variables, and duration of treatment effect. All active treatments were significantly more effective than placebo for many hourly measures and for the summary measures sum of pain intensity differences (SPID), sum of hourly pain relief values (TOTPAR), time to peak pain relief, and patient global assessment of study medication. The three ketoprofen doses were significantly more effective than placebo beginning at 30 minutes, whereas ibuprofen was significantly better than placebo beginning at 1 hour. A dose-response relationship was observed for ketoprofen, with the two higher doses providing significantly greater analgesia than the lower dose. However, a plateau effect was seen between the 12.5-mg and 25-mg dose levels. A significantly greater proportion of patients treated with each of the active treatments (ranging from 0.83 to 0.88) reported onset of relief compared with placebo (0.20). The distribution functions of onset of relief differed significantly among treatments, with ketoprofen 12.5 mg and 25 mg having a faster onset than ibuprofen 200 mg and ketoprofen 6.25 mg. The duration of effect was generally shorter for ketoprofen than for ibuprofen, and these difference were significant. This study provides evidence that at the dose levels of 12.5 mg and 25 mg, ketoprofen is an effective analgesic in providing relief of postoperative dental pain. Ketoprofen 12.5 mg and 25 mg provide significantly greater relief in the earlier time period, with a faster onset and shorter duration of effect than ibuprofen 200 mg. The two higher doses of ketoprofen provided similar analgesia, and no additional benefit was obtained by increasing the dose of ketoprofen to 25 mg. Therefore, we conclude that ketoprofen 12.5 mg is an appropriate dose for over-the-counter use.