eldavojohn writes "It's no secret what capsaicin, the fiery molecule of peppers, does to cell walls. In fact, it's now being used to open cells up to local anesthetics. Combine it with a new drug that works only from the insides of cells and you have a great system for relieving pain. From the article, 'QX-314 is known to reduce the activity of pain-sensing neurons in the nervous system and theoretically heighten pain thresholds. But there's a catch: Researchers found that "it wouldn't work from outside a nerve cell but it would work if you could get it inside," says Bruce Bean, a professor of neurobiology at Harvard Medical School and co-author of the new study."