This chapter offers an extensive review of anti-diabetic pharmacology, focusing on drugs commonly used in anaesthesia and critical care settings. The chapter commences with an overview of diabetes mellitus pathophysiology, highlighting essential concepts relevant to perioperative glucose management. It systematically explores major anti-diabetic medication classes, including insulin formulations, biguanides (metformin), sulfonylureas, meglitinides, thiazolidinediones, DPP-4 inhibitors, GLP-1 agonists, and SGLT-2 inhibitors. Each drug class is presented with detailed mechanisms of action, pharmacokinetics, clinical indications, dosing strategies, and associated adverse effects. Special attention is given to insulin management, discussing pharmacokinetic profiles of different insulin analogues and their perioperative considerations, including strategies for optimizing glycaemic control and minimizing risks of hypo- and hyperglycaemia. The chapter addresses critical safety considerations, potential drug interactions, and specific implications for anaesthesia management. By integrating theoretical knowledge with practical clinical guidance, this chapter equips trainees to manage diabetic patients safely and effectively, ensuring optimal perioperative outcomes.