Neuropathic pain is believed to be caused by changes in the nervous system that sustain pain even after an injury heals. In most cases, the injury that starts the pain involves the peripheral nerves or the central nervous system itself. It can be associated with trauma or with many different types of diseases, such as diabetes. There are many neuropathic pain syndromes, such as diabetic neuropathy, trigeminal neuralgia, postherpetic neuralgia (“shingles”), post-stroke pain, and complex regional pain syndromes (also called reflex sympathetic dystrophy or “RSD” and causalgia). Some patients who get neuropathic pain describe it as bizarre, unfamiliar pain, which may be burning or like electricity. The pain may be associated with sensitivity of the skin.