A comparative efficacy of amitriptyline, gabapentin, and pregabalin in neuropathic cancer pain: a prospective randomized double-blind placebo-controlled study

Abstract

Neuropathic pain is difficult to diagnose and difficult to treat with certainty. So the aim of the study was to evaluate comparative clinical efficacy of pregabaline with amitriptyline and gabapentin in neuropathic cancer pain. A total of 120 patients with cancer having severe neuropathic cancer pain were enrolled in the study after taking approval from Institutional Ethics Committee and divided in to 4 groups: group AT-amitriptyline, group GB-gabapentin, group PG-pregabalin, and group PL-placebo. Oral morphine was used for rescue analgesic for continued pain. Pain score (Visual Analogue scale) and secondary outcome measures such as intensity of lancinating, dysesthesia, and burning on numerical rating scale, Global satisfaction score (GSS), Eastern Co-operative Oncology Group scoring (ECOG), and adverse effects were assessed. At the end of study there was significant decrease in pain score in group PG as compared to the other groups; group AT (P = .003), group GB (P = .042), and group PL (P = .024). Percentage of patients with lancinating pain and dysesthesia were significantly less in group PG as compared to groups GB and PL. All the patients in group PL needed rescue morphine. After 4 visits, maximum improvement in ECOG scoring and GSS scoring was observed in group PG patients. Our results suggested that all antineuropathic drugs are effective in relieving cancer-related neuropathic pain. There was statistically and clinically significant morphine sparing effect of pregabaline in relieving neuropathic cancer pain and neuropathic symptoms as compared to other antineuropathic drugs.