A randomized controlled trial of ibuprofen versus ketorolac versus diclofenac for acute, nonradicular low back pain.

Objectives: Nonsteroidal anti-inflammatory drugs (NSAIDs) are the first-line medication for acute low back pain (LBP). It is unclear if the choice of NSAID impacts outcomes. We compared ibuprofen, ketorolac, and diclofenac for the treatment of acute, nonradicular LBP.

Methods: This was a three-armed, double-blind, comparative effectiveness study, in which we enrolled patients at the conclusion of an ED visit for musculoskeletal LBP and determined outcomes by telephone 5 days later. Patients were randomized to receive a 5-day supply of 600 mg of ibuprofen, 10 mg of ketorolac, or 50 mg of diclofenac, each to be used every 8 h as needed. Every participant also received LBP education. The primary outcome was improvement in Roland-Morris Disability Questionnaire (RMDQ), a 24-item instrument on which lower scores indicate better LBP functional outcomes, between ED visit and day 5. Secondary outcomes included pain intensity, measured using the descriptors none, mild, moderate, and severe, and the presence of stomach irritation.

Results: A total of 868 patients were screened and 66 patients were enrolled in each of the three arms. Baseline characteristics were similar. Improvements in RMDQ by day 5 were as follows: ibuprofen 9.4, ketorolac 11.9, and diclofenac 10.9 (p = 0.34). Mild or no pain on day 5 was as follows: ibuprofen 38 of 61 (62%), ketorolac 47 of 59 (80%), and diclofenac 45 of 62 (71%; 95% CI for rounded mean difference of 17% between ibuprofen and ketorolac = 1, 33%, p = 0.04, number needed to treat = 6 [95% CI = 3-69]). Stomach irritation was reported by 16 of 62 (26%) ibuprofen patients versus three of 61 (5%) in the ketorolac arm and six of 64 (9%) in the diclofenac arm (p < 0.01).

Conclusion: There were no important differences between groups with regard to the primary outcome. These data do not rule out that possibility that ketorolac results in better pain relief and less stomach irritation than ibuprofen.