Which diabetic medication is most associated with macular edema as a potential side effect?

• A. Glipizide
• B. Metformin
• C. Pioglitazone
• D. Glyburide

Answer: (C)

Macular edema can be linked to medications that cause fluid retention, and among common diabetes drugs, the thiazolidinedione class has the strongest association with this adverse effect. Pioglitazone, a TZD, is known to cause edema and has been reported in some cases to be associated with macular edema, making it the most likely drug to be linked to this condition in the list. Sulfonylureas like glipizide and glyburide mainly cause hypoglycemia and weight gain, not macular edema. Metformin’s notable issues are gastrointestinal upset and, rarely, lactic acidosis, with no strong link to macular edema.