The analgesic efficacy of single oral doses of drinkable diclofenac dispersible 50 mg was compared with that of ibuprofen 400 mg and placebo in a randomized, double-blind, parallel-group trial in 257 adult patients (245 valid for efficacy) with severe postoperative pain after extraction of an impacted lower third molar. In this study, pain intensity (on a 100-mm visual analog scale) and pain relief from baseline (using a five-point verbal rating scale) were assessed serially during an observation period of a hours. Intake of rescue analgesic was permitted in case of insufficient therapeutic effect; however at least 1 hour should have elapsed after test drug consumption. On the main efficacy variable, namely, reduction in the pain intensity score, both diclofenac dispersible (n = 83) and ibuprofen (n = 80) were statistically significantly (P <.01) superior to placebo (n = 82) starting at 20 and 40 minutes, respectively, after drug intake. The active medications were also significantly (P <.01) better than placebo for the secondary efficacy parameters viz. summed pain relief scores over 6 hours (TOTPAR-6); frequency of remedication with a rescue analgesic in the three treatment groups (diclofenac, 24%; ibuprofen, 28%; placebo, 65%); mean time to remedication; and global evaluation. All the treatments were well tolerated. Thus assay sensitivity of this trial (ibuprofen significantly better than placebo) has been demonstrated; in addition, diclofenac as a dispersible formulation has been shown to be an effective analgesic for the treatment of post-surgical dental pain.