Pilot study to evaluate the efficacy and tolerability of levetiracetam (Keppra) in treatment of patients with trigeminal neuralgia.

BACKGROUND AND PURPOSE: The objective of this study was to determine whether levetiracetam (LEV) is an effective drug for treatment of trigeminal neuralgia (TN).

METHODS: Ten patients with TN were enrolled in a 10-week, prospective, open-label pilot study. The primary outcome measure was the visual analogue scale on daily pain diary and side effects. Serum levels of LEV were measured to assess correlation between drug levels and pain control.

RESULTS: There was a significant tendency towards improvement in pain severity compared with baseline in four patients with higher doses of 4,000 mg/day. The four treatment responders had less pain compared with baseline (50-90% improvement) and three subjects continued the drug after study completion. All patients rated themselves on the global evaluation scale as much improved (n = 2), minimally improved (n = 3), no change (n = 1), minimally worse (n = 2), much worse (n = 1) and very much worse (n = 1). LEV was very well tolerated and there was no difference in side effects between the low and high doses of LEV evaluations.

CONCLUSION: Given its established safety profile, a randomized, placebo-controlled, double-blind trial of LEV using enhancement enrollment design is needed to confirm these open-labelled findings using a wide variety of outcome measures.