At Harvard Medical School, researchers are pouring pepper on pain in a way that could revolutionize anesthesia. Dr. Clifford Woolf, a Mass General specialist in pain management, and Harvard neurobiologist Bruce P. Bean invented a new approach to anesthesia that employs capsaicin – the stuff that makes chili peppers hot – to remove the pain from surgery without causing the numbness, wooziness, and partial paralysis that are unwelcome side effects of many procedures, from tooth extractions to childbirth.