Tramadol in neuropathic pain after spinal cord injury: a randomized, double-blind, placebo-controlled trial.

Objectives: To assess the efficacy and safety of tramadol for relieving neuropathic pain after spinal cord injury (SCI).

Methods: Thirty-six patients with SCI and neuropathic pain were enrolled in a randomized, double-blind, placebo-controlled trial, and 35 patients were included in the intention-to-treat analysis based on all patients taking at least 1 dose of study medication. Of the intention-to-treat population, 23 were randomized to treatment with tramadol and 12 to placebo. Patients were given study medication for 4 weeks, starting with 3 times 50 mg tramadol daily or 3 times 1 tablet of placebo.

Results: At evaluation, 4 weeks after the treatment initiation, ratings of pain intensity were lower in those randomized to tramadol compared with those on placebo. Pain severity scores on the Multidimensional Pain Inventory had also decreased in patients on tramadol. No between-group differences in pain affect were observed. Adverse events were substantial and caused 43% of those on tramadol and 17% on placebo to withdraw from the study.

Discussion: Tramadol might be tried for neuropathic pain after SCI after the use of gabapentin/pregabalin, and tricyclic antidepressants have been found to be insufficient. Titration should be slow and individual, to minimize the risk of adverse events.