Gabapentin in postamputation phantom limb pain: a randomized, double-blind, placebo-controlled, cross-over study

Area of Science:

• Neurology
• Pain Management
• Clinical Pharmacology

Background:

• Phantom limb pain affects a significant portion of amputees and is challenging to manage.
• Neuropathic pain conditions often respond to gabapentin.
• Evaluating gabapentin's efficacy for phantom limb pain is crucial.

Purpose of the Study:

• To assess the analgesic efficacy of gabapentin in patients experiencing phantom limb pain.
• To compare gabapentin monotherapy against placebo in a controlled study.

Main Methods:

• A randomized, double-blind, placebo-controlled, cross-over study involving patients with phantom limb pain.
• Gabapentin dosage was titrated up to 2400 mg daily, with a 6-week treatment period and a 1-week washout.
• Pain intensity was measured using the visual analog scale (VAS), with secondary measures including sleep, mood (HAD scale), and daily activities (Bartel Index).

Main Results:

• Gabapentin therapy resulted in a significantly greater reduction in VAS pain intensity difference compared to placebo (P = .03).
• No significant differences were observed between gabapentin and placebo for rescue medication use, sleep interference, depression, or daily living activities.
• Gabapentin was generally well-tolerated with minimal adverse effects reported.

Conclusions:

• Gabapentin monotherapy demonstrated superior efficacy over placebo in alleviating postamputation phantom limb pain after six weeks.
• No significant improvements were noted in mood, sleep, or activities of daily living, though a type II error is possible for these outcomes.