OGT Medications and Factors Affecting OGTT Results

Question 1

Which drug class is well-known for causing hyperglycemia that can produce a false-positive OGTT?

Accepted Answer

Corticosteroids

Answer

Corticosteroids (e.g., prednisone) raise blood glucose by stimulating hepatic gluconeogenesis and inducing insulin resistance, potentially producing false-positive OGTT results.

Question 2

Which antihypertensive class can mask hypoglycemic symptoms and potentially confound OGTT interpretation?

Accepted Answer

Beta-blockers

Answer

Beta-blockers suppress adrenergic symptoms of hypoglycemia (tremor, tachycardia) and can blunt the counter-regulatory glucose response, complicating OGTT interpretation.

Question 3

Thiazide diuretics affect OGTT results by:

Accepted Answer

Raising blood glucose by impairing insulin secretion and increasing insulin resistance

Answer

Thiazide diuretics cause hypokalemia, which impairs beta-cell insulin secretion, and can increase insulin resistance, leading to falsely elevated OGTT values.

Question 4

Niacin (nicotinic acid) at pharmacological doses used for dyslipidemia can affect OGTT by:

Accepted Answer

Raising plasma glucose through insulin resistance

Answer

High-dose niacin impairs insulin secretion and increases hepatic glucose output, potentially causing elevated OGTT values and new-onset diabetes.

Question 5

Which immunosuppressant used in organ transplant patients commonly causes post-transplant diabetes and abnormal OGTT?

Accepted Answer

Cyclosporine

Answer

Cyclosporine and tacrolimus (calcineurin inhibitors) are directly toxic to pancreatic beta cells and cause post-transplant diabetes mellitus (PTDM).

OGT - Oral Glucose Tolerance Practice Test

OGT - Oral Glucose Tolerance Practice Test

OGT Medications and Factors Affecting OGTT Results