Abstract
BACKGROUND: Major depressive disorder (MDD) affects over 332 million people globally. Although antidepressants are effective, adverse drug reactions (ADRs) may reduce adherence and quality of life (QoL). In Nepal, where mental health and pharmacovigilance (PV) systems are developing, assessing self-reported ADRs is essential. This study evaluated the antidepressant-induced ADRs among patients visiting the psychiatry outpatients department of a tertiary care hospital in Nepal. METHODS: A 3-month, single-center, cross-sectional study was conducted at the psychiatry outpatient department of Dhulikhel Hospital, Nepal. Using purposive sampling, 204 patients diagnosed with depression and receiving antidepressant therapy were assessed through structured interviews using validated tools like the Antidepressant Side-Effect Checklist (ASEC), Naranjo ADR Probability Scale, and Schumock and Thornton Criteria. RESULTS: Among 204 patients, the mean number of ADRs was 7.8 ± 6.2 per patient. Most participants were middle-aged (mean 42.8±11.2 years), urban residents (61.3%), and female (53.4%). Severe depression was the most frequent diagnosis (69.6%). Escitalopram (17.6%), amitriptyline (16.2%), and mirtazapine (14.7%) were most commonly prescribed. The most frequently reported ADRs were dry mouth (65.7%), blurred vision (61.3%), weight gain (59.8%), drowsiness (54.9%), and increased appetite (53.9%). Combination antidepressants therapy (26.9%) was associated with higher odds of increased appetite (adjusted odds ratio [AOR] 2.21, p < 0.05) and weight gain (AOR 1.87, p < 0.05). Naranjo assessment (mean score 2.1 ± 1.8) indicated that most ADRs were 'possible' (33.8%), a small proportion were 'probable' (3.4%), and none met criteria for 'definite' or 'doubtful'. All ADRs were predictable Type A reactions. The ASEC-based severity assessment showed most ADRs were mild (23.6%) to moderate (26.5%) with a lower proportion being severe (15.5%); thus, no treatment adjustments were made but counselling was provided as ADRs were clinically manageable through routine monitoring and counselling. CONCLUSION: Given the high frequency of predictable Type A ADRs and the increased metabolic effects observed with combination therapy, these findings emphasize the need for routine monitoring and strengthened PV practices to improve antidepressant safety in resource-limited settings like Nepal.