Adding ibuprofen and codeine to acetaminophen does not improve pain relief for acute musculoskeletal injury

Reference

Gong J, Colligan M, Kirkpatrick C, Jones P. Oral paracetamol versus combination oral analgesics for acute musculoskeletal injuries. Ann Emerg Med 2019;74(4):521-529.

Synopsis

These researchers recruited 119 patients who presented to an emergency department with an acute musculoskeletal injury (sprain, fracture, or contusion) with a pain score of at least 4 of a possible 10 (average 5.8) who were deemed by the treating physician not to require parenteral analgesia. The patients were randomly assigned to receive a single dose of 1000 mg acetaminophen, either with placebo or in combination with 400 mg ibuprofen and 60 mg codeine. Allocation to treatment was concealed from the clinician and researchers. Using intention-to-treat analysis, pain reduction at rest was similar in both groups after 1 hour: a decrease of 1.6 in the acetaminophen/placebo group and 2.0 in the combination analgesic group (difference = .4; P = .26). After 2 hours, pain reduction at rest was still similar with both treatments. Reduction in pain with activity was statistically greater with combination analgesia (3.0 vs 1.9; P = .04), but this difference, on average, did not meet the threshold for clinical relevance (a difference of 1.3). Almost 3 times as many (relative risk = 2.8) patients who received the combination reported a minor adverse effect than did patients who received acetaminophen alone. The study had a 90% power to find a difference at 60 minutes if one existed.