Final answer:
IDDM stands for Insulin-Dependent Diabetes Mellitus, which is Type 1 diabetes requiring exogenous insulin due to pancreatic insufficiency.
Step-by-step explanation:
The medical abbreviation IDDM stands for Insulin-Dependent Diabetes Mellitus. This is a term used to describe Type 1 diabetes, where the pancreas is unable to produce insulin, requiring individuals to manage their blood sugar levels with external sources of insulin. In a clinical setting, an insulin tolerance test may be conducted to confirm this type of diabetes. During the insulin tolerance test, hypoglycemia is a reaction observed relative to 0 hour in Insulin Dependent Diabetes Mellitus cases.