The Pharmacological Therapy of Chronic Neuropathic Pain

Chronic neuropathic pain, including painful peripheral polyneuropathy and post-herpetic neuralgia, affects 6.9-10% of the general population.

In this article, we present current treatment recommendations on the basis of a selective review of the literature.

Neuropathic pain does not respond consistently to classic non-opioid analgesic drugs and is better treated with co-analgesic, antidepressant, and anticonvulsant drugs and topical agents. Under certain conditions, however, neuropathic pain can be treated with opioids, even chronically. It was concluded in a large-scale m eta- analysis that tricyclic antidepressants, selective serotonin- norepinephrine reuptake inhibitors, and calcium-channel anticonvulsants are the drugs of first choice, with a number needed to treat (NNT) of 3.5-7.7 for a 50% reduction of pain. An analysis of all studies yielded an estimated publication bias of 10%. Treatment planning must include adequate consideration of the patient's age and comorbidities, concomitant medication, and potential side effects.

Drugs are now chosen to treat neuropathic pain independently of the cause and symptoms of the pain. Topical agents are used only to treat peripheral neuropathy. The utility of a treatment approach based on the patient's symptoms and pathological mechanisms was recently demonstrated for the first time in a randomized trial. The goal of current research is to facilitate treatment planning on the basis of the clinical phenotype.