RESUMO
BACKGROUND: The prevalence of addiction is increasing in the world. Methadone Maintenance Treatment (MMT) can be associated with severe stress and mild to moderate depressive symptoms. Vitamins and minerals are commonly found in multivitamins seem to improve mood. Therefore, the aim of this study was to evaluate the effect of multivitamins on anxiety and depression in patients undergoing MMT in a double-blind randomized controlled trial. METHODS: The study was designed as a double-blind, randomized controlled trial and involved 70 male MMT patients over the age of 18. Participants were randomized to one of two groups, either those receiving multivitamins or those receiving a placebo for 12 weeks. The multivitamin capsule included vitamin E, B1, B2, B3, B5, B6, B12, C, biotin, folic acid, and zinc. Anxiety and depression were measured using standard questionnaires, before and after the intervention. RESULTS: The between-group comparison (i.e., intervention vs. placebo) indicated there was no significant difference in anxiety scores; however, there was a significant between-group difference in depression scores, favoring the intervention group. CONCLUSIONS: Multivitamin supplementation improved depression but did not have a significant impact on anxiety in patients undergoing MMT.