The Pharmacological Therapy of Chronic Neuropathic Pain

Background: Chronic neuropathic pain, including painful peripheral polyneuropathy and post-herpetic neuralgia, affects 6.9-10% of the general population. Methods: In this article, we present current treatment recommendations on the basis of a selective review of the literature. Results: 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 meta-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. Conclusion: 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.