Compounded pain creams not better than placebo creams in localized chronic pain
A recent study has shown that compounded topical pain creams are only as effective as placebo creams in the treatment of localized chronic pain. Their costs are also higher compared with approved compounds, which should discourage routine use.
This randomized controlled trial included 399 patients with localized pain classified by each patient’s treating physician as neuropathic (n=133), nociceptive (n=133) or mixed (n=133). The following interventions were examined: pain creams compounded for neuropathic pain (ketamine, gabapentin, clonidine and lidocaine), nociceptive pain (ketoprofen, baclofen, cyclobenzaprine and lidocaine) or mixed pain (ketamine, gabapentin, diclofenac, baclofen, cyclobenzaprine and lidocaine), or placebo.
Average pain score 1 month after treatment was the primary outcome. A positive categorical response was defined as a decrease in pain score of ≥2 points plus a score of >3 on a 5-point satisfaction scale. Secondary outcomes included Short Form-36 Health Survey scores, satisfaction and categorical response. Participants with a positive outcome were followed through 3 months.
There were no differences in the mean reduction in average pain scores between the treatment and control groups for patients with neuropathic pain (–0.1 points; 95 percent CI, –0.8 to 0.5 points), nociceptive pain (–0.3 points; –0.9 to 0.2 points) or mixed pain (–0.3; –0.9 to 0.2 points), or for all patients (–0.3 points; –0.6 to 0.1).
A positive outcome was achieved in 72 patients (36 percent) in the treatment groups and 54 (28 percent) in the control group (risk difference, 8 percent; –1 to 17 percent) at 1 month.
The study was limited by the short follow-up period of only 1 month. Generalizability of results was also limited due to the heterogeneity among pain conditions and formulations of study interventions.