SAFETY AND EFFICACY OF MONOAMINE OXIDASE INHIBITORS IN THE TREATMENT OF ANXIETY DISORDERS: A SYSTEMATIC REVIEW AND META-ANALYSIS
Authors: Freire *Rafael , Fidry Marcos , Faria Clara , Cabo Mariana , Matos Ursula , Steffen Ricardo , Nardi Antonio 
Published: February 2025

Abstract

Background
Monoamine oxidase inhibitors (MAOI) are well known for its effectiveness on major depressive disorder. MAOI’ s prescription has been declining since the arrival of new antidepressant drugs, and there are few studies on their efficacy and safety in the treatment of anxiety disorders. MAOI are controversial drugs because, in one hand, their efficacy is potentially superior to other antidepressants, due to their distinct mechanism of action. On the other hand, there are concerns about safety of these medications.

Aims and Objectives
The authors performed a systematic review and meta- analysis to investigate the efficacy and safety of MAOI. We also looked for evidence of superiority over other stablished drugs.

Methods
MEDLINE, PsycINFO, Web of Science, EMBASE, The Cochrane Library, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov were searched for clinical trials using MAOI on anxiety disorders treatment, from January 1980 to May 2023. Review Manager 5 was used to analyze the effect size data, used as primary outcome.

Results
Over 2,972 records, 24 studies were included in the review. 19 studies were on social anxiety disorder treatment, 7 on panic disorder treatment. The studied MAOI were moclobemide, phenelzine, brofaromine and tranylcypromine. MAOI were superior to placebo in all 13 randomized controlled trials (RCT), except 2. MAOI were not superior to other antidepressants in comparative trials. They were effective on all 7 comparative trials and 4 open trials. 1,535 patients were pooled, only 6 (0.4%) showed severe adverse effects during trials. The risk of bias was high among the studies.

Discussion and Conclusion
MAOIs are effective treatments for social anxiety and panic disorders, although literature is scarce and there is high risk of bias. These medications demonstrated to be safe and effective. More clinical trials, with more stringent methodology are needed.

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