NAPLEX (North American Pharmacist Licensure Examination) Practice Exam

What is a contraindication for Metformin?

1. Hyperglycemia

2. eGFR < 30

3. Hypotension

4. Vitamin C deficiency

The correct answer is: eGFR < 30

A contraindication for Metformin is a lower estimated glomerular filtration rate (eGFR) of less than 30 mL/min/1.73m². Metformin is primarily eliminated by the kidneys, and in patients with impaired renal function, there is an increased risk of lactic acidosis associated with Metformin use. Therefore, patients with lower eGFR values should avoid Metformin to prevent this serious adverse effect. Hyperglycemia is actually an indication for Metformin use, as it is a medication commonly prescribed to help manage high blood sugar levels in patients with type 2 diabetes. Hypotension and Vitamin C deficiency are not known contraindications for Metformin use; they are not directly related to the safety or effectiveness of the drug.