Topical diclofenac offers no benefit over oral ibuprofen for acute low back pain

Topical diclofenac does not appear to significantly improve functional outcome in acute musculoskeletal low back pain as compared with oral ibuprofen, with no added benefit when co-administered with oral ibuprofen, according to a study.

The study included 198 adults (mean age 40 years, 36 percent women) who presented to the emergency department (ED) with acute, nontraumatic, nonradicular, musculoskeletal low back pain. These patients were randomly assigned to receive treatment with oral ibuprofen 400 mg plus placebo topical gel, diclofenac topical gel 1% plus oral placebo, or oral ibuprofen 400 mg plus diclofenac topical gel 1%.

The participants were asked to complete the 24-item Roland Morris Disability Questionnaire (RMDQ; maximum score 24, with higher scores indicating higher levels of pain-related disability).

The primary outcome was change in RMDQ score between ED discharge and 2 days later. Medication-related adverse events were evaluated by asking the participants whether the study medications caused any new symptoms.

Of the participants, 183 (92 percent) provided primary outcome data. The median RMDQ score at baseline was 18 (25th to 75th percentile: 13–22). The RMDQ score at 2 days following the ED visit had improved by 10.1 (95 percent confidence interval [CI], 7.5–12.7) with ibuprofen plus placebo group, by 6.4 (95 percent CI, 4.0–8.8) with diclofenac gel plus placebo, and by 8.7 (95 percent CI, 6.3–11.1) with ibuprofen plus diclofenac gel.

Analysis of the mean differences in RMDQ score between the treatment groups favoured the use of ibuprofen over diclofenac (mean difference, 3.7, 95 percent CI, 0.2–7.2). 

In terms of safety, medication-related adverse events occurred in 5 percent of patients who received ibuprofen, 2 percent of those who received diclofenac, and 6 percent of those who received both medications.