The anticonvulsant gabapentin (Neurontin) brought substantial pain relief to fibromyalgia patients in a new trial. Researchers randomly divided 150 patients into two groups of 75. One group took 1,200 or 2,400 mg/day; the other took a placebo. After 12 weeks, anyone who reported ≥30% less pain on the brief pain inventory (BPI) was counted as responsive.
Thirty-eight patients (51%) in the gabapentin group achieved that end point, compared with 23 patients (31%) on placebo. The gabapentin group also reported lower BPI severity scores (3.2 vs. 4.6), better sleep, and less fatigue than the placebo group (Arthritis Rheum. 2007;56:1336-1344).
“While gabapentin does not have FDA approval for fibromyalgia, I believe this study offers additional insight” to clinicians, says Stephen I. Katz, MD, PhD, director of the NIH’s arthritis division.Earlier this year, another drug used off-label proved effective for fibromyalgia—pregabalin (Lyrica), which is indicated for peripheral neuropathic pain. In a study of 745 patients, those taking pregabalin reported less pain and a better quality of life than those taking placebo. In June, the FDA added fibromyalgia to Lyrica’s indications. Both Lyrica and Neurontin are made by Pfizer.