The aim of the present placebo-controlled, crossover study was to evaluate the efficacy and pharmacokinetics of ibuprofen after a single oral dose of soluble ibuprofen 400 mg in 18 patients with postoperative pain after bilateral third molar surgery. Throughout a 5-hour investigation period, patients reported significantly less pain (P < 0.001) after treatment with soluble ibuprofen than after placebo. Peak plasma concentrations of ibuprofen occurred approximately 30 minutes after dosage. No significant correlations (P > 0.05) were observed between efficacy measures and the various pharmacokinetic parameters (AUC0-300, Cmax and Tmax) for ibuprofen after the soluble dose. It is concluded that a single dose of soluble ibuprofen 400 mg is an effective analgesic for the control of postoperative pain in the early period after third molar surgery. Efficacy of this preparation does not appear to be directly related to the drug's pharmacokinetic variables in plasma.