The document provides an extensive overview of diabetes mellitus, detailing its complications which are classified into acute and long-term categories affecting various organ systems. Acute complications include hypoglycemia and diabetic ketoacidosis (DKA), while long-term complications involve microvascular (e.g., retinopathy and nephropathy) and macrovascular issues (e.g., cardiovascular disease). Effective management strategies and patient education for preventing and treating these complications are also discussed.