A double-blind randomized trial was carried out in 59 patient suffering from moderately severe to severe strains and sprains to compare the efficacy of 4-(p-fluorophenyl)-1-isopropyl-7-methyl-2(1H)-quinazolinone (fluproquazone) in the relief of pain. Patients received either 50 mg or 100 mg fluproquazone up to 6 times daily for 3 days. The results of subjective assessments showed that after 2 days pain had either completely resolved or markedly improved in all patients. Both treatments were equally effective in relieving both spontaneous pain and pain on movement after 1 and 2 days. No differences were found between the two groups in the patients' overall evaluation of treatment or physicians' assessment of therapeutic response. Both dosage were well tolerated during the short-term trial.