Background: Adverse drug reaction, usually reported by pharmacovigilance, either through health care professionals or the patients themselves is of utmost importance to give an accurate estimate of the severity of the drug and also if the ADRs are casual, preventable or severe.Methods: A total of 42 patients satisfied the WHO definition of ‘adverse drug reactions’ were included in the study. The demographic details were taken, and the regular physical examination and clinical examination was done for all the patients. The latest drug they were on and the dosage were analyzed and the type of reaction was assessed. The causality, severity and preventability were also assessed.Results: Majority of the ADRs were found in the medicine department, followed pulmonology, obstetrics-gynecology and paediatrics. B-lactams were the major cause of ADRs with 42.2%, followed by NSAIDs with 23.8%, fluoroquinolones with 19% and 9.5% due to antitubercular drugs. 66.7% of the ADRs were mild, 28.6% were moderate and 4.8% were severe. The most common type of ADR were skin rashes (40.5%), urticara (16.7%), headaches (26.2%), insomnia (21.4%), diarrhoea (21.4%), abdominal pain (14.3%) and vomiting (4.8%). Most of the ADRs were evaluated as probably preventable (69%), definitely preventable (26.2%), non preventable (4.8%).Conclusions: Most of the drug reactions are mild and preventable. More health care professionals as well as patients need to be aware of the drug reactions at much early age so as to prevent the condition before it becomes serious.