The Effect of Zinc Supplementation on Relapse of Anxiety and Depression in Opioid-Dependent Patients Treated with Methadone

Abstract

Background: The human body contains 2 to 3 mg of zinc, with the highest concentrations found in the hippocampus, amygdala, and frontal cortex, which are associated with emotions. Additionally, studies have shown that taking zinc supplements improves mood in individuals undergoing antidepressant treatment as well as in the general population. Objectives: The present study aimed to evaluate the efficacy of zinc supplementation in reducing the likelihood of anxiety and depression relapse in opioid-dependent patients undergoing methadone maintenance treatment. Patients and Methods: A descriptive cross-sectional study was conducted on opioid-dependent patients undergoing methadone treatment. Participants were divided into groups based on the random block permutation method: The case group [treated with zinc supplements for 3 months (n = 32)] and the control group [treated with a placebo for 3 months (n = 31)]. Inclusion criteria included receiving methadone maintenance therapy (MMT), absence of major neurological and underlying diseases, and absence of medications that reduce serum zinc levels. Exclusion criteria included a history of allergy to zinc-containing compounds and taking zinc supplements before the intervention. The measurement tools included a demographic questionnaire and Beck’s Anxiety and Depression Inventory. Data were analyzed using SPSS version 26, with a P-value of < 0.05 deemed statistically significant. Results: In the case group, a significant improvement in quality of life, specifically in physical health, mental health (MH), and social health, was observed compared to the control group after zinc supplementation (P < 0.05). After three months of zinc supplementation, anxiety, stress, and depression levels significantly decreased in the case group compared to the control group (P < 0.05). Conclusions: Zinc supplementation significantly helped reduce anxiety and depression symptoms in patients receiving methadone maintenance treatment.