The efficacy of gabapentin in migraine prophylaxis: an observational open label study.

Migraine is often a chronic and disabling disorder. The objective of our study was to assess the efficacy and safety of gabapentin in the prophylaxis of migraine in patients refractory to other prophylactic treatments. The study included 67 migraine patients, 55 women and 12 men; 52 patients completed this prospective, open-label study. Patients were given 900-1800 mg of gabapentin in 3 doses; the mean duration of treatment was 7.2 months. Reduction in the number of days with headache, pain intensity and number of acute medications was assessed through patient diary. The mean number of migraine days/4 weeks was reduced from 15.8 to 8.6, yielding a reduction of 7.2 migraine days/4 weeks (P=0.001). Pain intensity was reduced by 25% in 14 (26.9%), by 50% in 29 (55.7%) and by 75% in three (5.7%) patients, whereas no improvement was reported by six (11.5%) patients at the end of follow up. A significant reduction was recorded in acute medication use (P=0.001). Adverse events were reported by 32/67 (47.8%) patients, in 15 (22.4%) of them causing discontinuation of the drug. The most frequently reported adverse events were drowsiness, dizziness and slowness. Prophylactic treatment with gabapentin was found to be associated with a significant reduction in the number of days with headache, use of acute medications and pain intensity.