In a study of 144 patients, with Grade 1 and 2 inversion injuries to the ankle sustained in sport, treatment with a non-steroidal anti-inflammatory was considerably superior to placebo with respect to joint tenderness, level of training and injury severity. No difference in efficacy could be determined between ibuprofen 2400 mg given in two or four equally divided daily doses. Ten patients withdrew from the study because of side effects, five from ibuprofen twice daily, three from ibuprofen four times daily and two from the placebo group. This study confirms the efficacy, flexibility and tolerability of high dose ibuprofen.