Hot peppers — the spicy kind — are part of a promising new approach to pain relief that appears to block pain without also disrupting thinking, balance or body awareness. Not only can these side effects of painkillers be unsafe, they also complicate the treatment of chronic and acute pain.
A new study found that the chemical that makes chili peppers hot, when combined with another molecule, blocks pain-sensing neurons in rats without impairing important neurological functions such as motor movement or touch. The finding may lead to a new generation of safer, more targeted pain blocking medicines.
"The Holy Grail in pain science is to eliminate pathologic pain without impairing thinking, alertness, coordination, or other vital functions of the nervous system. This finding shows that a specific combination of two molecules can block only pain-related neurons. It holds the promise of major future breakthroughs for the millions of persons who suffer with disabling pain," says Story C. Landis, Ph.D., director of the National Institute of Neurological Disorders and Stroke (NINDS) at the NIH. which funded the research along with the National Institute of Dental and Craniofacial Research (NIDCR) and the National Institute of General Medical Sciences (NIGMS).
The study, published in the October 4, 2007, issue of Nature, found that a combination of two particular drugs can block pain-sensing neurons in rats without impairing important neurological functions such as motor movement or touch.
The two drugs used were capsaicin — the chemical that makes chili peppers hot — and a drug called QX-314. This combination blocked the activity of pain-sensing neurons without interfering with other signals. Most conventional pain-relievers block activity in all types of neurons, causing numbness, paralysis and other disturbances, and accounting for many of the health risks associated with painkillers.