Abstract
Type 2 Diabetes Mellitus (T2DM) is a global health challenge characterised by pathophysiological diversity, resulting in significant inter-individual variability in drug response. Pharmacogenomics (PGx) offers a powerful approach to personalise T2DM management by linking genetic makeup to therapeutic efficacy and safety. Traditional treatments such as metformin, sulfonylureas, and insulin remain central to management but often present limitations, including adverse effects and declining effectiveness. A comprehensive literature search was conducted across the PubMed, Scopus, and Web of Science databases, covering publications from 2010 to 2025. Search words included "type 2 diabetes," "pharmacogenomics," "drug response," "genetic polymorphism," and "precision medicine". Peer-reviewed studies investigated gene-drug interactions and their underlying mechanisms. Pathways and clinical correlations were critically examined. Emphasis was placed on validated pharmacogenomic markers affecting major antidiabetic drug classes-biguanides,sulfonylureas, thiazolidinediones, incretin-based agents, and SGLT2 inhibitors-while also highlighting emerging genomic associations of exploratory relevance. We outline how genetic diversity influences drug response, moving from pharmacogenetics to broader pharmacogenomic studies that scan the entire genome to identify novel drug targets and deepen the understanding of T2DM pathophysiology. Genomic and electronic health data from large populations have become increasingly available, presenting a transformative opportunity for research and precision medicine within the healthcare system. To effectively utilise genomic information in clinical practice, it is essential to establish a framework for assessing the validity and clinical utility of genomic data and patient electronic health records. This review summarises current evidence, identifies implementation challenges, and discusses future directions to help bridge the gap between pharmacogenomic discoveries and personalised diabetes care.