A Randomized, Double-Blind, Placebo-Controlled Trial of Ibuprofen Lysinate in Comparison to Ibuprofen Acid for Acute Postoperative Dental Pain

INTRODUCTION: Ibuprofen acid is poorly soluble in the stomach, thus reaching maximum plasma levels at approximately 90 min post-dose. Ibuprofen lysinate has been developed to accelerate absorption of ibuprofen to shorten the time to analgesic efficacy. This study compared analgesic efficacy and onset of effect of a single dose of ibuprofen lysinate or ibuprofen acid in patients undergoing third molar extraction. METHODS: Randomized, double-blind, placebo-controlled, multi-center, parallel-group single-dose study. Adults (18-60 years) undergoing extraction of ≥ 1 third molar were randomized 2:2:1 to ibuprofen lysinate, ibuprofen acid, or placebo postoperatively. Pain relief (PAR, 5-point scale, 0 = none to 4 = complete pain relief) and pain intensity (PI, 100 mm visual analog scale) were assessed between 15 and 360 min post-dose. The primary endpoint was the weighted sum of PAR scores at 6 h (TOTPAR). Time to onset of effect, global assessment of efficacy, and adverse events were also assessed. RESULTS: Overall, 351 patients received ibuprofen lysinate (N = 141), ibuprofen acid (N = 139), or placebo (N = 71). Both active treatments significantly reduced pain compared with placebo, from 15 min post-dose to 6 h (TOTPAR: ibuprofen lysinate: 19.57; ibuprofen acid: 19.96; placebo: 8.27). Ibuprofen lysinate was significantly more effective than placebo, but non-inferior to ibuprofen acid, at providing pain relief over 6 h. There was no significant difference between ibuprofen lysinate and ibuprofen acid for onset of analgesia. Both ibuprofen formulations were well tolerated; all adverse events were mild to moderate and considered unrelated to treatment. CONCLUSIONS: A single dose of ibuprofen lysinate is non-inferior to ibuprofen acid in terms of analgesic efficacy, onset of action, and tolerability in patients who have recently undergone dental surgery. TRIAL REGISTRATION: EudraCT No. 2006-006942-33. Plain language summary available for this article.