Every year, 200,000 patients in the United States develop shingles, for which there is no cure. Shingles (herpes zoster) is a viral infection that causes a painful rash. It often appears as a band of blisters that typically affects the trunk/torso. Other parts of the body may be involved such as the neck, face, scalp or limbs. The pain from shingles can be excruciating, and the cause might not be immediately evident. The virus lies inactive in all persons who have been infected with chickenpox, and decades later, the virus can reappear as shingles. While some patients have mild cases and recover fully, other patients suffer from post-herpetic neuralgia, a painful syndrome that often cannot be adequately treated with pain-relieving medications.