USMLE Endocrine Pharmacology Practice
Exam Questions Correct Answers, and
Detailed Explanations for Computer
Science Students||Already Graded A+
1. A 45-year-old woman with hypothyroidism is started on levothyroxine.
Which of the following best describes its mechanism of action?
A) Direct activation of thyroid-stimulating hormone receptors
B) Conversion to T3 and binding nuclear thyroid hormone receptors
C) Inhibition of iodine organification in the thyroid
D) Blocking peripheral T4 to T3 conversion
Answer: B
Levothyroxine (T4) is converted to the active form T3, which binds nuclear
thyroid hormone receptors to regulate gene transcription.
2. Which drug is preferred for the management of hyperthyroidism in the first
trimester of pregnancy?
A) Methimazole
B) Propylthiouracil (PTU)
C) Radioactive iodine
D) Levothyroxine
Answer: B
PTU is preferred in the first trimester due to a lower risk of teratogenic effects
compared with methimazole. Radioactive iodine is contraindicated in
pregnancy.
3. A patient develops agranulocytosis while on antithyroid therapy. Which drug
is most likely responsible?
A) Levothyroxine
B) Methimazole
C) Liothyronine
D) Radioactive iodine
,Answer: B
A rare but serious adverse effect of methimazole is agranulocytosis, requiring
discontinuation of therapy.
4. Which of the following is a rapid-acting insulin?
A) NPH
B) Glargine
C) Lispro
D) Detemir
Answer: C
Insulin lispro is a rapid-acting insulin used to control postprandial glucose
spikes.
5. Which drug used in type 2 diabetes decreases hepatic glucose production
and increases insulin sensitivity?
A) Glipizide
B) Metformin
C) Pioglitazone
D) Acarbose
Answer: B
Metformin primarily reduces hepatic gluconeogenesis and improves insulin
sensitivity without causing hypoglycemia.
6. A 60-year-old man with type 2 diabetes has persistent postprandial
hyperglycemia. Which drug delays carbohydrate absorption in the gut?
A) Metformin
B) Acarbose
C) Glipizide
D) Sitagliptin
Answer: B
Acarbose is an α-glucosidase inhibitor that slows intestinal carbohydrate
absorption, reducing postprandial glucose spikes.
, 7. Which oral antidiabetic drug works by stimulating pancreatic insulin release?
A) Metformin
B) Glipizide
C) Pioglitazone
D) Exenatide
Answer: B
Glipizide, a sulfonylurea, stimulates insulin secretion from pancreatic β-cells.
8. Which class of drugs activates PPAR-γ to improve insulin sensitivity?
A) Sulfonylureas
B) Thiazolidinediones
C) Biguanides
D) GLP-1 agonists
Answer: B
Thiazolidinediones, such as pioglitazone, activate PPAR-γ to increase peripheral
glucose uptake.
9. A patient on GLP-1 receptor agonist therapy may experience which effect?
A) Hypoglycemia alone
B) Increased gastric emptying
C) Weight loss
D) Hyperinsulinemia without glucose lowering
Answer: C
GLP-1 receptor agonists slow gastric emptying, enhance glucose-dependent
insulin secretion, and promote weight loss.
10. Which drug is a DPP-4 inhibitor used in type 2 diabetes?
A) Sitagliptin
B) Exenatide
C) Metformin
D) Pioglitazone
Exam Questions Correct Answers, and
Detailed Explanations for Computer
Science Students||Already Graded A+
1. A 45-year-old woman with hypothyroidism is started on levothyroxine.
Which of the following best describes its mechanism of action?
A) Direct activation of thyroid-stimulating hormone receptors
B) Conversion to T3 and binding nuclear thyroid hormone receptors
C) Inhibition of iodine organification in the thyroid
D) Blocking peripheral T4 to T3 conversion
Answer: B
Levothyroxine (T4) is converted to the active form T3, which binds nuclear
thyroid hormone receptors to regulate gene transcription.
2. Which drug is preferred for the management of hyperthyroidism in the first
trimester of pregnancy?
A) Methimazole
B) Propylthiouracil (PTU)
C) Radioactive iodine
D) Levothyroxine
Answer: B
PTU is preferred in the first trimester due to a lower risk of teratogenic effects
compared with methimazole. Radioactive iodine is contraindicated in
pregnancy.
3. A patient develops agranulocytosis while on antithyroid therapy. Which drug
is most likely responsible?
A) Levothyroxine
B) Methimazole
C) Liothyronine
D) Radioactive iodine
,Answer: B
A rare but serious adverse effect of methimazole is agranulocytosis, requiring
discontinuation of therapy.
4. Which of the following is a rapid-acting insulin?
A) NPH
B) Glargine
C) Lispro
D) Detemir
Answer: C
Insulin lispro is a rapid-acting insulin used to control postprandial glucose
spikes.
5. Which drug used in type 2 diabetes decreases hepatic glucose production
and increases insulin sensitivity?
A) Glipizide
B) Metformin
C) Pioglitazone
D) Acarbose
Answer: B
Metformin primarily reduces hepatic gluconeogenesis and improves insulin
sensitivity without causing hypoglycemia.
6. A 60-year-old man with type 2 diabetes has persistent postprandial
hyperglycemia. Which drug delays carbohydrate absorption in the gut?
A) Metformin
B) Acarbose
C) Glipizide
D) Sitagliptin
Answer: B
Acarbose is an α-glucosidase inhibitor that slows intestinal carbohydrate
absorption, reducing postprandial glucose spikes.
, 7. Which oral antidiabetic drug works by stimulating pancreatic insulin release?
A) Metformin
B) Glipizide
C) Pioglitazone
D) Exenatide
Answer: B
Glipizide, a sulfonylurea, stimulates insulin secretion from pancreatic β-cells.
8. Which class of drugs activates PPAR-γ to improve insulin sensitivity?
A) Sulfonylureas
B) Thiazolidinediones
C) Biguanides
D) GLP-1 agonists
Answer: B
Thiazolidinediones, such as pioglitazone, activate PPAR-γ to increase peripheral
glucose uptake.
9. A patient on GLP-1 receptor agonist therapy may experience which effect?
A) Hypoglycemia alone
B) Increased gastric emptying
C) Weight loss
D) Hyperinsulinemia without glucose lowering
Answer: C
GLP-1 receptor agonists slow gastric emptying, enhance glucose-dependent
insulin secretion, and promote weight loss.
10. Which drug is a DPP-4 inhibitor used in type 2 diabetes?
A) Sitagliptin
B) Exenatide
C) Metformin
D) Pioglitazone
