Psychotropic drugs in the management of chronic pain syndromes.

Psychotropic drugs have been integrated into the management of chronic pain syndromes for more than 30 years. Numerous open and controlled studies have taken place evaluating especially the antinociceptive efficacy of antidepressive drugs. This survey comprises the results of clinical reports, open clinical studies, placebo-controlled studies, and comparative studies of different substances. It will be shown that antidepressants are by far the best evaluated psychopharmacological substances, showing superiority against placebo in 70% of a total of 67 placebo-controlled studies. The synopsis of controlled comparison studies of different antidepressants tends to demonstrate a superiority of clomipramine; however, the number of comparative studies is too small to draw final conclusions, especially because a number of methodological shortcomings reduce the comparability of different studies. The literature is concerning the pharmacological mechanisms and the interaction of antidepressive and antinociceptive effects of antidepressants is reviewed. Finally, treatment guidelines are formulated, which summarize the recommendations of the international literature.