Hot New Pain Treatment: Chili Peppers Fiery Ingredient Dripped Into Wounds WASHINGTON -- Biting the bullet could soon be replaced with something more edible. Scientists are testing the chemical that gives chili peppers their fire to see if it can ease the pain of surgery. Doctors are dripping an ultra-purified version of capsaicin into open wounds during knee replacement and a few other highly painful operations. The volunteers are under anesthesia so they don't scream at the initial burn. The hope is that bathing surgically exposed nerves in a high enough dose will numb them for weeks, so patients suffer less pain and require fewer painkillers as they heal. Besides surgery, Harvard University researchers are mixing capsaicin with another anesthetic in hopes of developing epidurals that wouldn't confine women to bed during childbirth or dental injections that don't numb the whole mouth.