1
ATI PHARMACOLOGY NGN PROCTORED
EXAM 2025 – 100% CORRECT ANSWERS | A+
GRADED | REVISED 2019 VERSION
Multiple-Choice Questions
Mechanism of Action
1. What is the primary mechanism of action of lisinopril in treating hypertension?
A. Blocks calcium channels
B. Inhibits angiotensin-converting enzyme (ACE)
C. Promotes sodium reabsorption
D. Stimulates beta-adrenergic receptors
Correct Answer: B
Rationale: Lisinopril, an ACE inhibitor, prevents the conversion of angiotensin I to
angiotensin II, reducing vasoconstriction and blood pressure.
2. How does metformin manage blood glucose levels in type 2 diabetes?
A. Stimulates insulin release
B. Increases hepatic glucose production
C. Decreases intestinal glucose absorption
D. Blocks glucagon secretion
Correct Answer: C
Rationale: Metformin decreases hepatic glucose production and intestinal glucose
absorption while improving insulin sensitivity.
3. What is the mechanism of action of albuterol in treating asthma?
A. Inhibits histamine release
B. Stimulates beta-2 adrenergic receptors
C. Blocks muscarinic receptors
D. Reduces leukotriene production
Correct Answer: B
Rationale: Albuterol, a short-acting beta-2 agonist, relaxes bronchial smooth muscles,
improving airflow.
4. How does warfarin exert its anticoagulant effect?
A. Inhibits platelet aggregation
B. Activates antithrombin
C. Inhibits vitamin K-dependent clotting factors
D. Enhances fibrin breakdown
Correct Answer: C
Rationale: Warfarin inhibits the synthesis of vitamin K-dependent clotting factors (II,
VII, IX, X) in the liver.
5. What is the mechanism of action of furosemide in treating edema?
A. Inhibits sodium-potassium ATPase
B. Blocks sodium reabsorption in the loop of Henle
, 2
C. Promotes potassium excretion in the distal tubule
D. Increases glomerular filtration rate
Correct Answer: B
Rationale: Furosemide, a loop diuretic, inhibits sodium and chloride reabsorption in the
loop of Henle, promoting diuresis.
6. How does levothyroxine treat hypothyroidism?
A. Inhibits thyroid hormone synthesis
B. Replaces deficient thyroid hormones
C. Stimulates TSH release
D. Blocks iodine uptake
Correct Answer: B
Rationale: Levothyroxine is a synthetic T4 hormone that replaces deficient thyroid
hormones to restore metabolic balance.
7. What is the primary action of ondansetron in preventing nausea?
A. Blocks dopamine receptors
B. Inhibits serotonin (5-HT3) receptors
C. Stimulates histamine receptors
D. Enhances GABA activity
Correct Answer: B
Rationale: Ondansetron, an antiemetic, blocks 5-HT3 receptors in the chemoreceptor
trigger zone and GI tract.
8. How does atorvastatin lower cholesterol levels?
A. Inhibits HMG-CoA reductase
B. Increases bile acid excretion
C. Blocks cholesterol absorption
D. Enhances lipoprotein lipase activity
Correct Answer: A
Rationale: Atorvastatin, a statin, inhibits HMG-CoA reductase, reducing cholesterol
synthesis in the liver.
9. What is the mechanism of action of morphine in pain management?
A. Blocks sodium channels
B. Activates opioid receptors
C. Inhibits cyclooxygenase
D. Enhances serotonin release
Correct Answer: B
Rationale: Morphine binds to mu-opioid receptors, altering pain perception and
response.
10. How does tamoxifen treat breast cancer?
A. Inhibits estrogen receptor activity
B. Blocks progesterone synthesis
C. Enhances aromatase activity
D. Promotes apoptosis of all cells
Correct Answer: A
Rationale: Tamoxifen is a selective estrogen receptor modulator that inhibits estrogen
activity in breast tissue, slowing cancer growth.
ATI PHARMACOLOGY NGN PROCTORED
EXAM 2025 – 100% CORRECT ANSWERS | A+
GRADED | REVISED 2019 VERSION
Multiple-Choice Questions
Mechanism of Action
1. What is the primary mechanism of action of lisinopril in treating hypertension?
A. Blocks calcium channels
B. Inhibits angiotensin-converting enzyme (ACE)
C. Promotes sodium reabsorption
D. Stimulates beta-adrenergic receptors
Correct Answer: B
Rationale: Lisinopril, an ACE inhibitor, prevents the conversion of angiotensin I to
angiotensin II, reducing vasoconstriction and blood pressure.
2. How does metformin manage blood glucose levels in type 2 diabetes?
A. Stimulates insulin release
B. Increases hepatic glucose production
C. Decreases intestinal glucose absorption
D. Blocks glucagon secretion
Correct Answer: C
Rationale: Metformin decreases hepatic glucose production and intestinal glucose
absorption while improving insulin sensitivity.
3. What is the mechanism of action of albuterol in treating asthma?
A. Inhibits histamine release
B. Stimulates beta-2 adrenergic receptors
C. Blocks muscarinic receptors
D. Reduces leukotriene production
Correct Answer: B
Rationale: Albuterol, a short-acting beta-2 agonist, relaxes bronchial smooth muscles,
improving airflow.
4. How does warfarin exert its anticoagulant effect?
A. Inhibits platelet aggregation
B. Activates antithrombin
C. Inhibits vitamin K-dependent clotting factors
D. Enhances fibrin breakdown
Correct Answer: C
Rationale: Warfarin inhibits the synthesis of vitamin K-dependent clotting factors (II,
VII, IX, X) in the liver.
5. What is the mechanism of action of furosemide in treating edema?
A. Inhibits sodium-potassium ATPase
B. Blocks sodium reabsorption in the loop of Henle
, 2
C. Promotes potassium excretion in the distal tubule
D. Increases glomerular filtration rate
Correct Answer: B
Rationale: Furosemide, a loop diuretic, inhibits sodium and chloride reabsorption in the
loop of Henle, promoting diuresis.
6. How does levothyroxine treat hypothyroidism?
A. Inhibits thyroid hormone synthesis
B. Replaces deficient thyroid hormones
C. Stimulates TSH release
D. Blocks iodine uptake
Correct Answer: B
Rationale: Levothyroxine is a synthetic T4 hormone that replaces deficient thyroid
hormones to restore metabolic balance.
7. What is the primary action of ondansetron in preventing nausea?
A. Blocks dopamine receptors
B. Inhibits serotonin (5-HT3) receptors
C. Stimulates histamine receptors
D. Enhances GABA activity
Correct Answer: B
Rationale: Ondansetron, an antiemetic, blocks 5-HT3 receptors in the chemoreceptor
trigger zone and GI tract.
8. How does atorvastatin lower cholesterol levels?
A. Inhibits HMG-CoA reductase
B. Increases bile acid excretion
C. Blocks cholesterol absorption
D. Enhances lipoprotein lipase activity
Correct Answer: A
Rationale: Atorvastatin, a statin, inhibits HMG-CoA reductase, reducing cholesterol
synthesis in the liver.
9. What is the mechanism of action of morphine in pain management?
A. Blocks sodium channels
B. Activates opioid receptors
C. Inhibits cyclooxygenase
D. Enhances serotonin release
Correct Answer: B
Rationale: Morphine binds to mu-opioid receptors, altering pain perception and
response.
10. How does tamoxifen treat breast cancer?
A. Inhibits estrogen receptor activity
B. Blocks progesterone synthesis
C. Enhances aromatase activity
D. Promotes apoptosis of all cells
Correct Answer: A
Rationale: Tamoxifen is a selective estrogen receptor modulator that inhibits estrogen
activity in breast tissue, slowing cancer growth.