The project is evaluating the analgesic efficacy of amitriptyline at two doses in comparison to placebo for the mamagement of chronic orofacial pain; to determine an optimal dose to be used; and to determine the mechanism of action of antidepressants in pain management. A double-blind incomplete cross-over design of drug administration is used and each subject is administered in two four-week periods, separated by a two week washout, one of the following: placebo, high dose amitriptyline, or low dose amitriptyline. Both high dose (up to 150 mg) and low dose (10-30 mg) of amitriptyline result in significant pain relief in comparison to placebo. Amitriptyline reduced depression scores in the depressed patients but not in non-depressed patients, providing evidence that its analgesic effect is not associated with a parallel change in mood.
