Gabapentin for Postherpetic Neuralgia Pain

Gabapentin has been shown to be well tolerated and effective in the management of postherpetic neuralgia (PHN) pain. This study looked at whether the occurrence and frequency of adverse events with gabapentin correlates with increasing doses of the drug. Gabapentin was begun at 300 mg/d and increased to maintenance doses of 1800 to 3600 mg/d by day 12 to 24. The study included data from 603 patients with PHN: 358 patients received gabapentin and 245 received placebo. The 3 most common adverse events were dizziness, drowsiness, and peripheral edema. In this analysis, the incidence of peripheral edema was increased when gabapentin was given at 1800 mg/d or more. Dizziness and drowsiness, the other most commonly occurring adverse events, were transient and did not occur more frequently or worsen with dosages of 1800 mg/d or greater. Based on these findings, it does not appear that safety concerns should limit the dosage of gabapentin to achieve optimal efficacy. Parsons B. Tive L. Huang S. “Gabapentin: a pooled analysis of adverse events from three clinical trials in patients with postherpetic neuralgia.” American Journal Geriatric Pharmacotherapy. 2(3):157-62, 2004 Sep.