Objectives: This study was conducted to identify and report the adverse drug reactions (ADRs) which are occurring in pediatric and medicine departments in a tertiary care hospital at Vadodara. Methods: A cross-sectional study was conducted for 6 months in-patient at a tertiary care teaching hospital. We enrolled the patients based on inclusion criteria and data was analyzed with the help of MS excel 7 and Graph pad Prism. Further, the assessments of type, severity, and preventability of reported ADRs were done using Wills and Brown classification, modified Schumock and Thornton severity scale, modified Hartwig and Siegel preventability scale. Results: Data were collected from a total of two hundred patients of which twenty-six (13%) patients were affected with ADRs. Among twenty-six patients, females (64%) were more affected with ADRs when compared to males (36%). According to the department, most ADRs were observed in the medicine ward than in the pediatric. The highest number of ADRs was associated with antibiotics (46.1%). Based on the type of ADRs, Type B ADRs (77%) were more observed followed by Type A (7%) and Type C (8%). Conclusions: The information obtained from our study will help clinical pharmacists and healthcare professionals to take precautions in the future and adopt certain measures for preventing the ADRs and hence help in promoting safer and rational drug use in institutions and improving the quality of patient care.