Neuropathic pain is frequently caused by damage to the peripheral nerves. Symptoms may include burning or shooting sensations, and abnormal sensitivity to normally non-painful stimuli. Neuropathic pain is difficult to treat. Anticonvulsants and antidepressants are frequently used but their use is limited by side effects. Tramadol is a unique pain killing drug with mild opiate properties.
In the update of this review undertaken in November 2008, five randomised controlled trials involving a total of 374 participants met the inclusion criteria for this review and compared tramadol to placebo. Evidence from these trials showed that 100 to 400 mg of tramadol is an effective symptomatic treatment for peripheral neuropathic pain. One trial involving less than 40 participants compared tramadol to morphine, and one involving 21 participants compared tramadol to clomipramine. It was not possible to draw conclusions from these two trials as to which of these drugs is more effective.
Treatment with tramadol may cause side effects, including constipation, nausea, sedation and a dry mouth, all of which resolve after stopping treatment. In the trials reviewed here, one person out of eight treated with tramadol left the trial because of side effects. Tramadol is also associated with a small risk of seizures (fits) and its use is contraindicated in people with a history of epilepsy.