Introduction. Migraine is a frequent and disabling pathological condition with important socioeconomic repercussions. Recent studies have explored the use of antiepileptic drugs in the prophylactic treatment of migraine. Preliminary studies effectiveness and safety have shown that gabapentin is a drug that is effective and well-tolerated by patients. Aim. To evaluate thee, of gabapentin in the prophylactic treatment of migraine. Patients and methods. A prospective, open, multicentre, random clinical study, carried out according to IHS criteria, which compares the effectiveness and safety of gabapentin in 1,200 mg/day and2, 000 mg/day doses as a preventive treatment for migraine over a 16-week period. Results. Significant differences were found in patients treated with gabapentin, as compared with their basal state, in the following: a lower number of attacks (reduction in weeks 4, 10 and 16: -2.4 +/- 2.8, -2.9 +/- 2.9 and -3.1 +/- 2.9 attacks/month on a basal rate of 5.3 +/- 3.5 attacks/month), lower intensity (on a scale of 0-3 of increasing pain intensity: basal rate: 2.7 +/- 0.4, week 4: 1.8 +/- 0.9, week 10: 1.7 +/- 0.9, week 16: 1.4 +/- 1.0) and how long the pain lasts (basal rate 390 hours/month, week 4: 180 hours/month, week 10: 180 hours/month, week 16: 120 hours/month). No statistically significant differences were found between doses of 1, 2 00 or 2, 000 mg/day. Mild adverse effects were seen in 62 patients (37.8%): drowsiness (22.6%), asthenia (7.9%), dizziness (4.9%), abdominal pain (3.7%) and dazedness (3.7%). No serious adverse events occurred. Conclusions. Gabapentin can be considered an effective and safe drug in the preventive treatment of migraine.