USMLE STEP 1 PRACTICE QUESTION #44
TOPIC: Type 2 Diabetes Pharmacology
Today’s question was created based on the somewhat challenging nature of type 2 diabetes pharmacology. It will test your ability to recognize the commonly used DM2 pharmaceuticals and how they work. This is a 2nd order question. The essential details of this question can be found in the “general analysis” section below. Good luck!
A 44-year-old female is seeing her primary care physician four months after being diagnosed with type 2 diabetes. Despite her efforts to maintain a healthy lifestyle, her hemoglobin A1c is 9.0%. As a result, she is prescribed the most suitable medication. Which of the following is true of the prescribed medication?
A) It decreases peripheral insulin sensitivity
B) It does not affect postprandial glucose levels
C) It poses no risk of hypoglycemia
D) It may cause weight gain
E) It may cause metabolic alkalosis in high-risk individuals
Detailed Breakdown of Answers + Correct Answer Below ⏬
ANSWER + QUESTION BREAKDOWN
The basic mental model for this week’s question comes from our detailed test-taking skills masterclass. Here’s the thought process behind this 2nd order question:
Step 1. Identify what the question asks (identify the true statement about the prescribed medication). Since the medication isn't provided, we must identify it based on the patient’s diagnosis.
Step 2. Read the vignette and diagnose the condition or problem.
Step 3. Name the 1st line medication used to improve her condition.
Step 4. Since the potential answer to “Which of the following is true of the medication she was prescribed?” could be many things, look to the answers and find one that matches most appropriately with your determined 1st line medication.
GENERAL ANALYSIS
This question involves a 44-year-old female with type 2 diabetes who, despite lifestyle modifications, has an elevated hemoglobin A1c level. She is prescribed the first-line medication for type 2 diabetes, which is likely metformin. The question asks which statement about this medication is true.
ANSWER CHOICES:
ANSWER CHOICE A: It decreases peripheral insulin sensitivity
Decreasing peripheral insulin sensitivity would worsen glucose control; this is not an appropriate feature of a diabetic medication.
ANSWER CHOICE B: It does not affect postprandial glucose levels
Managing postprandial glucose levels is an essential feature of effective diabetes management. The ideal diabetic medication should decrease postprandial glucose levels.
ANSWER CHOICE C: It poses no risk of hypoglycemia
Hypoglycemia is an unlikely consequence of a medication that does not increase insulin secretion.
ANSWER CHOICE D: It may cause weight gain
Weight gain is a possible side effect of some diabetes medications. The drug of choice for DM2 is associated with weight neutrality or modest weight loss, not weight gain.
ANSWER CHOICE E: It may cause metabolic alkalosis in high-risk individuals
Metabolic alkalosis is an unlikely consequence of the most appropriate medication for DM2. Rare cases, however, may result in lactic acidosis, especially if the patient has renal impairment.
FINAL VERDICT…
Metformin is the most commonly prescribed first-line medication for type 2 diabetes. It works primarily by decreasing hepatic glucose production and improving insulin sensitivity, mainly in peripheral tissues like muscle. Unlike insulin or insulin secretagogues (such as sulfonylureas), metformin does not stimulate insulin secretion, which means it does not cause hypoglycemia when used alone. This makes it a safe option for avoiding hypoglycemia—an advantage in the management of type 2 diabetes. Metformin is also associated with weight neutrality or modest weight loss, benefiting patients who may struggle with weight management.
CORRECT ANSWER: C) It poses no risk of hypoglycemia
Metformin’s mechanism of action (big-picture): Suppresses glucose production in the liver. The hypothesized MOA is as follows:
• Metformin inhibits mitochondrial respiratory-chain complex 1 (results in reduced ATP & increased AMP)
• Increased AMP activates adenosine monophosphate-activated protein kinase (AMPK)
• Increased AMPK works via two mechanisms: 1) Phosphorylates CBP & CRTC2 transcription factors (inhibits genes involved in glucose production), and 2) Inhibits mitochondrial glycerol-3-phosphate dehydrogenase (increased cytosolic NADH stimulates the conversion of pyruvate to lactate and simultaneously decreases gluconeogenesis).
NOTE: While rare, metformin can cause lactic acidosis in some patients.
PS… If you're ready to bust through the challenges, struggles, and/or fears you’re facing as you navigate medical school, it’s time to get an ALL-ACCESS PASS:
Full access to all new & archived Qs, tips & tools, Q&As ($5,000 value; my 1-on-1 coaching fee)
Weekly LIVE ZOOMS with Dr. Paul ($500/week value)
Instant access to our USMLE Step 1 & Step 2 CK drills books ($200 value)
Access to BONUS insider tips & tricks you won’t get anywhere else (priceless!)
Plus, you'll never miss out on new training, tips, or strategies to take your career to the next level. All for just $47 a month! Click below to subscribe and go all-access.