As a running interest from someone who helps treat pain for a living as an anesthesiologist, I find this information utterly fascinating. Check out this article from WPTV.com out of West Palm Beach, Florida about more research involving capsaicin and analgesia:

Hot Sauce Numbs Knee Pain

Last Update: 3/19 10:16 am

REPORT: MB #2808

BACKGROUND: Capsaicin is the active component found in chili peppers and is being studied for its pain relieving properties. Capsaicin is generally viewed as an irritant for most mammals, causing a burning sensation on the tissue it comes in contact with. The idea behind using capsaicin for pain relief is when applied to an area of the body, the nerves are overwhelmed by a burning sensation and are unable to report pain for an extended amount of time.

Nerve cells that sense a type of long-term throbbing pain have a receptor called TRPV1. Capsaicin binds to that receptor and opens it to enter only those pain fibers — and not other nerves responsible for other kinds of pain or other functions like movement. These so-called C neurons also sense heat; thus capsaicin’s burn. But when TRPV1 opens, it lets extra calcium inside the cells until the nerves become overloaded and shut down. That’s how the numbness is achieved.

The form of capsaicin used for surgical pain relief is an ultra purified form called Adlea. This purified version is used to avoid infection and is administered while the patient is under anesthesia so he or she cannot feel the initial burn.

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