Pain Management Research Yielding More Treatment Options

"There have been some tremendous advances in implantable technology to address chronic pain states, and they are already on the market," Binit Shah, M.D., a psychiatrist and fellowship-trained pain specialist at Cleveland's University Hospitals Case Medical Center, said during a recent interview. One is a spinal-cord stimulator.

"Such devices are getting more sophisticated and showing better results," Sunil Panchal, M.D., an anesthesiologist, Johns Hopkins-trained pain specialist, and president of the Coalition for Pain Education Foundation in Lutz, Fla., reported. "We can now treat someone's pain and essentially eliminate the need for pain medications."

Some exciting advances in the pharmaceutical management of pain are also taking place, Shah and Panchal pointed out (see Psychiatrists' Expertise Useful in Managing Chronic Pain).

One concerns the anti-inflammatory molecule interleukin. Researchers are looking into ways of injecting interleukin into the spinal fluid of patients to counter molecules that lead to chronic pain or neuropathic pain states.

Another concerns immunocompetent cells of the central nervous system called glia and receptors on them called toll-like receptors (TLR). Glia play a role in initiating and maintaining pain responses. In animal models, giving a TLR antagonist countered longstanding neuropathic pain to a substantial degree.

Another advance involves sodium-ion channels in nerves. Most anticonvulsants used to alleviate neuropathic pain do so by blocking sodium-ion channels in nerves. Yet drugs are now being developed that can block the sodium-ion channels in nerves that carry pain signals without affecting the sodium-ion channels in other nerves. As a result, they should be much more specific in their pain-fighting action than the anticonvulsants now used and have fewer side effects. Such drugs might reach the market within "another five or six years if the testing goes well and there aren't any unforeseen toxicity issues," Panchal suggested. "Also, since they are not in the opioid class, they shouldn't have the issues that go along with opioids."

Although psychiatrists will probably not be implanting devices into patients to counter chronic pain, they should certainly be able to take advantage of new pain medications that come on the market, Shah and Panchal believe.