Comparative Efficacy of Oral Ibuprofen-Arginine, Intramuscular Magnesic Dipyrone and Placebo in Patients with Postoperative Pain Following Total Hip Replacement

The comparative clinical efficacy and tolerability of oral ibuprofen-arginine 400mg, intramuscular dipyrone 2g and placebo were assessed in the control of postoperative pain in 106 patients who underwent surgery for a total hip replacement. Pain intensity was assessed at baseline and at 10, 20, 30, 45, 60, 90, 120, 180, 240 and 300 minutes after treatment on a visual analogue scale ranging from no pain (0mm) to unbearable pain (100mm). Pain intensity was reduced in both active treatment groups from mean levels of 63mm (ibuprofen-arginine) and 62mm (dipyrone) to 22mm and 17mm, respectively, with a decrease of approximately 70% at the end of the study period, showing a decrease of 50% after the first 60 minutes. In contrast, pain levels in the placebo group (57.8mm) were reduced to 36.6mm within the first hour and to 32mm (<50%) at the end of the study. The peak pain intensity difference from baseline in patients receiving oral ibuprofen-arginine, intramuscular dipyrone and placebo was 51, 50 and 35mm, respectively. Statistically significant differences were observed between active treatments and placebo, but not between active treatments. No significant differences were observed between treatment groups with regard to the number of patients requesting rescue medication. 56% of patients of the ibuprofen-arginine group, 66% of the dipyrone group and only 21 % of the placebo group rated their medication as excellent or very good. With regard to tolerability, during the whole study period only 2 cases of headache were reported, one in the ibuprofen-arginine group and one in the placebo group. Data from this study showed that oral ibuprofen-arginine exhibits similar analgesic efficacy to intramuscular dipyrone. Therefore, oral ibuprofen-arginine may prove to be a useful alternative to parenteral analgesic agents in the treatment of postoperative pain following total hip replacement.