Objectives: This study aimed to investigate the frequency of adverse drug reactions (ADRs) in patients with type 2 diabetes mellitus (T2DM) undergoing treatment with different combinations of antidiabetic medications, focusing on regimens containing alpha-glucosidase inhibitors. Methods: This prospective, non-randomized, open-label study was conducted at Varun Arjun Medical College & Rohilkhand Hospital, Uttar Pradesh, with a sample size of 240 patients in six treatment groups. The occurrence of ADRs was recorded, and the severity was classified according to the Hartwig and Siegel scale. Results: The total number of ADRs reported was 47 by 24 study subjects accounting for 10% of the sample population. Flatulence was the most common ADR reported (25.53%), followed by hypoglycemia (23.4%). No severe ADRs were reported across the groups, with most reactions being mild (95.74%). The highest number of ADRs was observed in Group-II (Metformin).