A pharmacologist at Southern Illinois University School of Medicine, Springfield, has received a $1.4 million grant from the National Institute of Drug Abuse to study a new chronic pain treatment.
Louis Premkumar, PhD, associate professor of pharmacology, is the principal investigator for the project. The research will study a new drug, Resiniferatoxin (RTX), as a potential treatment for chronic, debilitating, terminal pain in patients such as those with bone cancer or large mass abdominal cancer where other drugs are not effective. (Currently the only treatment for human patients with such chronic pain is morphine, which has severe side effects.)
RTX is an ultra-potent capsaicin compound - a form of the irritant that gives chili peppers their ‘fire’. It is extracted from the sap of a highly irritating, cactus-like plant native to Morocco, and is some 1,000 times more potent than the capsaicin in chilis.
Chili-derived capsaicin is used in topical preparations, for example, to temporarily numb neurons in a pain-messaging system responsible for heat-related, inflammatory pain - while RTX ‘shatters’ and kills these cells.
The first experiments with RTX involved dogs suffering from painful bone cancer. After an RTX injection in the spinal cord they were able to move and play again, apparently pain free, for weeks to months. Because RTX burns before deadening pain, injections require general anesthesia.
• Southern Illinois University School of Medicine news release, Nov 3, 2009
• “Fiery pepper may hold key to easing pain,” AP, 2008, by Lauran Neergaard.
• Wikipedia - Resiniferatoxin http://en.wikipedia.org/wiki/Resiniferatoxin