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Mild neuropathic pain may be alleviated by a variety of analgesics available "over-the-counter" such as aspirin, acetaminophen (e.g., Tylenol), or ibuprofen (e.g., Advil; Motrin).

Other Drugs

• Dextromethorphan is commonly used as a non-prescription cough suppressant. Studies in a limited number of patients indicate a significant improvement in pain scores for patients with diabetic neuropathy who were treated with dextromethorphan. Side effects may include:

  • sedation (up to 70% of patients)
  • memory impairment
  • ataxia (reduced motor coordination)

• Nerve Block

A nerve block involves the injection of a drug (such as steroids, opioids, or local anesthetics) directly into the area of an affected nerve in an attempt to interrupt the transmission of pain signals to the brain. Although some patients with peripheral neuropathy report relief from pain following a nerve block, most studies indicate that the therapeutic value of the injections is short-lived.

Topical Agents

There are two topical agents that may be used, namely capsaicin and lidocaine patch.

Capsaicin

This topical agent is extracted from chili peppers and depletes substance P from sensory nerves in the skin. Results for neuropathic pain are inconsistent. Efficacy for diabetic neuropathy may be moderate (some report up to 90% reduction on pain scores) with improvement seen in other quality of life parameters including work, sleep, and daily functioning. There are indications that capsaicin is as effective as amitriptyline for reducing pain and improving the quality of life for patients with diabetic neuropathy but without systemic side effects.

Capsaicin is available over-the-counter at a strength of 0.075%. The most common side effect is burning or pain when first administered but this subsides over time. It is important not to rub your eyes after administering capsaicin since contact with the eyes will cause considerable burning and could cause eye damage. Some people have reported coughing, sneezing, or respiratory irritation due to the residue or fumes that remain following the application of capsaicin. These symptoms can be minimized by applying capsaicin in a well ventilated room.

Topical Lidocaine

This drug is available as a patch and is approved by the FDA for treatment of postherpetic neuralgia. It appears to be less effective for other neuropathic pain which usually extends over an area much larger than the size of the patch. It may be beneficial for placement at sites of particularly intense pain.

Other Treatments

Some types of peripheral neuropathy, particularly those related to immunologic etiology, may require other treatment modalities, for example:

• Guillain-Barre syndrome - treatment includes intravenous immunoglobulin therapy (IVIG) and/or plasmapheresis (partial removal of plasma from the blood which is then returned to the circulatory system) to help hasten recovery and reduce long-term disability.
• Chronic inflammatory demyelinating polyneuropathy (CIDP) - treatment includes immunotherapy, immunosuppressive agents such as cyclophosphamide, steroids, and/or plasmapheresis.
• Multifocal motor neuropathy - treatment includes IVIG and immunosuppressive agents
• Vasculitis related to mononeuropathy multiplex is treated with corticosteroids and other immunosuppressive agents such as cyclophosphamide.

Summary of Drug Therapy Recommendations for Peripheral Neuropathy

To date, there have been no formal standard guidelines regarding drug therapy for peripheral neuropathy that reflect the addition of Lyrica and Cymbalta which were recently approved for treatment of diabetic peripheral neuropathy by the U.S. Food and Drug Administration. The conclusions of an article appearing in 2003 in the New England Journal of Medicine (Volume 348; pp. 1243-1255, March 26, 2003) were as follows: