Antidepressant-induced analgesia in chronic non-malignant pain: a meta-analysis of 39 placebo-controlled studies

Abstract

For 39 controlled studies on the analgesic effect of antidepressants, a meta-analysis was conducted to get an estimation of the effect size, and to obtain a sight on the possible modes of action and the methodology used. The mean size of the analgesic effect was 0.64. It means that the average chronic pain patient who received an antidepressant treatment had less pain than 74% of the chronic pain patients who received a placebo. This quantification, however, is only as good as the studies on which it is based, and it could be differentiated for each of the pain syndromes and antidepressants examined. Real analgesic qualities of antidepressive agents seemed to offer the most plausible and economical explanation for the effect, but the predominant importance of serotonin reuptake blocking was not confirmed. Finally, the meta-analysis appeared to be fruitful for the generation of new hypotheses, for making some recommendations for future research, and for proposing some provisional guidelines for the clinical use of antidepressants in chronic non-malignant pain.

Usefulness of Antidepressants for Improving the Neuropathic Pain-Like State and Pain-Induced Anxiety through Actions at Different Brain Sites

“…Firm evidence has shown that tricyclic antidepressants (TCAs) should be considered the gold standard treatment for neuropathic pain (Coluzzi and Mattia, 2005;Sindrup et al, 2005). It has also been reported that the analgesic effect of antidepressants is independent of their antidepressive action, and occurs at lower doses and with a faster onset of action in a clinical situation (Pilowsky et al, 1982;Onghena and Van Hondenhobe, 1992;Richeimer et al, 1997). This effect can be explained by several pharmacological mechanisms.…”

Antidepressant Drugs and Pain

“…Moreover, some authors have proposed that SSRIs may enhance the process underlying acute pain (Dirksen R, 1998). A meta-analysis of antidepressant-induced analgesia by Onghena and colleagues found that selective NRIs were no more efficacious than dualaction antidepressants (Onghena & Van Houdenhove, 1992). However, based on the evidence described here, we can conclude that drugs that inhibit the reuptake of monoamines are likely to be effective in the treatment of chronic pain.…”

“…Several studies have demonstrated the intrinsic analgesic effects of antidepressants (McQuay et al, 1996;Onghena & Van Houdenhove, 1992;Smith et al, 1998). However, it remains unclear whether antidepressants are efficacious for the treatment of all types of pain or only for specific subtypes.…”

Analgesic effects of antidepressants alone and after their local co-administration with morphine in a rat model of neuropathic pain

“…It was estimated that tricyclic antidepressants are effective in the model of neuropathic pain evoked by ligation of the sciatic nerve in rats [39]. Currently it is under consideration that antidepressant drugs act not only as mood elevators but also analgesics in chronic pain syndromes [40]. The antidepressant amitriptyline is used as an adjuvant in the treatment of a variety of chronic pain conditions.…”