Side effects of diabetes drugs. Conceptual image of drugs on conveyor belts marked with myocardial infarction (heart attack), heart failure, and stroke (cerebrovascular accident), with diabetic patients at top. The conveyor belt for heart failure has a red light on it, representing the increased risk of this condition as a side effect of some of the drugs used to lower glucose levels in those with diabetes. The green lights may represent drugs shown not to increase the risk of those conditions, or used to treat those conditions. Diabetes is a condition where the body is resistant to or fails to produce the insulin needed to break down sugars in the blood. Insulin or drugs can be used to lower the blood sugar to normal levels.