Analgesia: Are Acetaminophen/NSAID Combinations More Effective Than One Drug Alone?

Although many clinicians recommend combining acetaminophen (paracetamol) and nonsteroidal anti-inflammatory drugs (NSAIDs) for acute pain management, the evidence for this practice has been mixed. An international team of investigators performed a systematic review of all randomized controlled trials (RCTs) in which paracetamol/NSAID combinations were compared to either class of drug alone for managing acute postoperative pain. The study was funded by the manufacturer of a paracetamol/ibuprofen combination tablet.

Twenty RCTs involving 1852 patients compared paracetamol/NSAID combinations with paracetamol alone. An analgesic combination was more effective than acetaminophen alone for at least one of three measures (pain score, need for supplemental analgesia, globally assessed pain relief) in 16 studies (80%). The mean reduction in pain intensity was 35%, and the mean reduction in need for supplemental analgesics was 39%. Fourteen studies involving 1129 patients compared the efficacy of an analgesic combination to that of an NSAID alone. Nine studies (64%) demonstrated that the combination was more effective. The mean reduction in pain intensity was 38%, and the mean reduction in need for analgesic supplementation was 31%. The incidence of side effects did not differ significantly between combination therapy and either single-drug therapy.