Pregabalin or morphine and gabapentin for neuropathic pain

Common causes of neuropathic pain are diabetes and herpes zoster, with 15% of patients with long-standing diabetes and 11% of herpes patients suffering from this pain. Gabapentin and pregabalin modulate the α2δ calcium-channel subunits, possibly decreasing the neurotransmitter release associated with the central sensitisation that occurs in neuropathic pain. Gabapentin has been shown to be effective in neuropathic pain and, recently, so has pregabalin. These agents seem to have similar efficacy when used alone, but this needs to be tested in a head-to-head trial. A clinical trial comparing morphine, gabapentin or their combination at lower doses showed that the combination of morphine and gabapentin reduced the pain score to a greater extent than either agent alone. This combination treatment represents a novel approach to neuropathic pain.