COMPARATIVE ASSESSMENT OF ADVERSE DRUG REACTIONS IN TYPE 2 DIABETES MELLITUS PATIENTS RECEIVING MONOTHERAPY VERSUS COMBINATION THERAPY: A PROSPECTIVE OBSERVATIONAL STUDY IN A TERTIARY CARE HOSPITAL

Abstract

Background: Type 2 diabetes mellitus (T2DM) is a progressive metabolic disorder that almost always demands lifelong pharmacotherapy, and as the disease advances patients are frequently escalated from single-agent to multi-agent regimens. Both approaches carry a risk of adverse drug reactions (ADRs), yet real-world comparative safety data remain limited. Objectives: To compare the pattern, severity and outcome of ADRs in T2DM patients receiving monotherapy versus combination therapy in a tertiary care hospital. Methods: A prospective, comparative, observational study was carried out over four months in the general medicine and surgery wards of a tertiary care teaching hospital. Forty consenting adults with T2DM were enrolled by universal sampling and divided equally into a monotherapy group (n=20) and a combination therapy group (n=20). ADRs were captured through case-sheet review, patient interview and treatmentchart analysis, and were graded for severity using the modified Hartwig and Siegel scale. Data were summarised as frequencies and percentages, and the two groups were compared using the chi-square (or Fisher exact) test, with p<0.05 taken as significant. Results: The cohort was predominantly elderly (50% aged 60 years or above) with a slight male preponderance (52.5%). A total of 43 ADRs were recorded among the 40 patients. Hypoglycaemia was by far the commonest reaction (90.70%), occurring in 46.51% of events in the monotherapy group and 44.19% in the combination group. Seizure and hypokalaemia (2.33% each) were confined to monotherapy, whereas dizziness and vomiting (2.33% each) occurred only with combination therapy. Overall, monotherapy accounted for a marginally higher share of ADRs (51.16% versus 48.84%). Most reactions were moderate in severity (95.3%), and every reaction resolved completely (100% recovery). Conclusion: Hypoglycaemia dominated the safety profile of antidiabetic therapy and was somewhat more frequent with single-agent regimens, underscoring the need for individualised dosing, structured glucose monitoring and pharmacist-led counselling. Combination therapy produced a slightly wider but milder spectrum of reactions, supporting its rational use when tighter glycaemic control is required.