Drug derived from hot peppers relieves post-shingles pain

The thousands of people who suffer from postherpetic neuralgia (PHN), the severe burning pain that often follows the skin infection commonly known as shingles, now have new, durable relief from an unexpected source: capsaicin, the alkaloid that makes hot peppers hot.

According to the results of a multi-center study headed by Miroslav Backonja, a neurologist with UW Hospital and Clinics, high-concentration applications of trans-capsaicin work to activate, then deactivate the skin receptors that produce the painful, post-shingles burning. Backonja presented the results of his study to the annual meeting of the American Academy of Neurology in San Francisco on April 29.

Over the course of several weeks, patients were given one-hour applications of a patch containing high concentrations of capsaicin, and then asked to assign a numerical score to their pain. Following each treatment, patients reported a more than 30 percent progressive reduction in pain; in certain cases, patients who received only a single treatment of capsaicin were able to experience a full year free of pain.