Which of the following represents main categories of antidiabetic medications that do not directly modify insulin therapy?

• A. Metformin; SGLT2 inhibitors; GLP-1 receptor agonists; DPP-4 inhibitors; thiazolidinediones
• B. Insulin secretagogues
• C. SGLT2 inhibitors only
• D. Antihyperlipidemics

Answer: (A)

The key idea is recognizing drug classes that lower blood glucose without requiring or adjusting exogenous insulin dosing. Metformin reduces hepatic glucose production and improves peripheral insulin sensitivity, so glucose falls even though no insulin dose is changed. SGLT2 inhibitors act in the kidney to promote glucose loss in the urine, a mechanism that does not depend on insulin. GLP-1 receptor agonists mimic incretin effects to boost glucose-dependent insulin release, slow gastric emptying, and promote satiety, again without administering insulin. DPP-4 inhibitors enhance the body’s own incretin hormones to increase insulin secretion in a glucose-dependent way, without giving insulin. Thiazolidinediones improve how well tissues respond to insulin, lowering glucose through improved insulin sensitivity rather than altering insulin doses.

Other options don’t fit as well for this question. Insulin secretagogues stimulate the pancreas to release more insulin, which changes endogenous insulin dynamics rather than offering a separate non-insulin approach. Antihyperlipidemics address lipids rather than hyperglycemia. A single class like SGLT2 inhibitors only would omit other major non-insulin categories.

So the collection of metformin, SGLT2 inhibitors, GLP-1 receptor agonists, DPP-4 inhibitors, and thiazolidinediones represents the main non-insulin antidiabetic options.