Type 2 diabetes mellitus (T2DM) significantly increases colorectal cancer (CRC) risk, driven by shared metabolic and inflammatory pathways. As lifelong glucose-lowering medications are routinely used in T2DM, their pharmacological activities and associated oncological effects have become critical for safety and repurposing. This review systematically summarizes the pharmacological mechanisms, epidemiological evidence, and clinical outcomes of eight antidiabetic drug classes in modulating CRC ris