Ann Neurol. 1981 Feb; 9(2): 101-6.

Pain II: new approaches to management.

Fields HL.

There is an intrinsic analgesia system in the brain with both endogenous opioid and biogenic amine links. This system provides a basis for understanding how different therapeutic approaches relieve pain. The present review critically evaluates the analgesic efficacy of the following therapies: placebo administration, transcutaneous electrical nerve stimulation, acupuncture, intrathecal and epidural opiate injection, electrical stimulation of the brain, and psychotropic drugs.