Background: Adverse drug reactions (ADRs) are the prime determinants of non-adherence to drugs. In psychiatric care even, the normal doses can elicit severe adverse responses, that may adversely affect the outcome of treatment. Materials & methods: This was a Longitudinal observational study conducted during august 2020 in male ward of psychiatric hospital. The causality assessment of documented ADRs was done using Naranjo scale, and WHO-The Uppsala Monitoring Centre probability scale, severity was assessed using Hartwig et al. scale, and preventability assessment using Modified Schumock and Thornton's Scale.   Out of 81 patients, 79 patients were reported with ADR and a total of 79 ADRs were identified. The most common were acidity, gastritis, somnolence. Based on the causality assessments as per Naranjo Algorithm most of the ADRs were found to be probable and that of WHO-UMC scale were certain. According to severity assessment done using modified Hartweig & Seigel scale majority of the ADRs were moderate and as per Schumock Thronton scale for preventability more than half of the ADRs were definitely preventable. Conclusion:  This study provides an insight into ADR pattern among psychiatric in-patients. A high frequency of ADRs were seen in the inpatients of psychiatry settings, particularly of moderate nature and most likely preventable sorts. Psychiatric drugs are more likely to develop ADRs when to compared to anti-epileptics and sedative drugs. Continuous monitoring and assessment of patients using psychiatric drugs may help to improve patient safety.