Does gabapentin (Neurontin) help prevent episodic migraine?
Gabapentin does not decrease the frequency of migraine headaches and is not recommended for prophylactic therapy. (Strength of Recommendation: B, based on inconsistent or limited-quality patient-oriented evidence.)
Worldwide, migraine has a lifetime prevalence of 18% in women and 10% in men.1 Therapeutic options are usually divided into prophylactic and abortive. Avoidance of triggers may be beneficial. Effective prophylaxis can range from acupuncture to medications such as propranolol, topiramate (Topamax), and valproic acid (Depakene), all of which have shown consistent positive benefit in systematic reviews.2–5
Previously published systematic reviews by these same authors gave cautious support for the use of gabapentin for migraine prophylaxis based on poor-quality evidence. However, new data from not-yet-published industry-sponsored trials of gabapentin for migraine have come to light during litigation against the drug manufacturer. These data have led the authors to change their conclusion based on the results of five studies involving 1,009 patients.
Four trials with a total of 351 patients compared gabapentin in a dosage of 900 to 2,400 mg per day with placebo. The meta-analysis found no significant reduction in the frequency of migraine headache (mean difference in the number of headaches = −0.44; 95% confidence interval, −1.43 to 0.56). Pooled results of two studies with 235 patients comparing the proportion of responders (at least 50% improvement in frequency of headaches) between those treated with up to 2,400 mg of gabapentin vs. placebo failed to show a difference (odds ratio = 1.59; 95% confidence interval, 0.57 to 4.46). One study analyzed prophylactic use of the prodrug gabapentin enacarbil (Horizant) titrated up to 3,000 mg daily and failed to find any benefit.
Patients taking gabapentin often reported adverse effects, most commonly dizziness (number needed to harm [NNH] = 7), drowsiness (NNH = 9), and abnormal thinking (NNH = 20).
According to the Quality Standards Subcommittee of the American Academy of Neurology and the American Headache Society, prophylaxis should be offered to anyone whose daily activities are severely impaired, or when acute drug treatment is inadequate. The antiepileptic drugs topiramate and valproic acid are considered first-line prophylactic agents. However, the guidelines state that the evidence is inadequate to recommend the use of gabapentin for migraine prevention.6 Because gabapentin is not effective and commonly causes adverse effects, family physicians should consider alternatives when offering prophylaxis for migraine headache.