HESI Pharmacology RN
Exam | 2025/2026 Verified
Questions & A+ Correct
Answers
1. Antibiotics: A client with a penicillin allergy is prescribed erythromycin for
streptococcal pharyngitis. What is the primary mechanism of action?
A) Inhibits cell wall synthesis B) Inhibits protein synthesis C) Disrupts DNA
replication D) Inhibits folic acid synthesis B) Inhibits protein synthesis Rationale:
Erythromycin, a macrolide, binds to the 50S ribosomal subunit, inhibiting
bacterial protein synthesis; contraindicated in clients with QT prolongation due to
risk of torsades de pointes; interacts with CYP3A4 inhibitors like ketoconazole,
increasing levels.
2. Antihypertensives: Lisinopril is prescribed for hypertension. The nurse
should monitor for which adverse effect due to its mechanism?
A) Hyperkalemia B) Hypoglycemia C) Bradycardia D) Constipation A)
Hyperkalemia Rationale: As an ACE inhibitor, lisinopril blocks angiotensin II
formation, reducing aldosterone and potassium excretion; contraindicated in
pregnancy (fetal renal damage); interacts with potassium-sparing diuretics,
exacerbating hyperkalemia.
3. Analgesics: A client post-op receives IV morphine. What is the primary
contraindication?
A) Renal impairment B) Respiratory depression C) Liver failure D)
Hypothyroidism B) Respiratory depression Rationale: Morphine, an opioid
agonist, binds mu-receptors, causing analgesia but suppressing respiration;
mechanism involves CNS depression; interacts with CNS depressants like
benzodiazepines, increasing overdose risk; monitor RR <12/min.
,4. Anticoagulants: Warfarin therapy requires monitoring of INR. What
interaction increases bleeding risk?
A) Vitamin K-rich foods B) Cranberry juice C) St. John's wort D) Grapefruit juice
B) Cranberry juice Rationale: Warfarin inhibits vitamin K-dependent clotting
factors; cranberry inhibits CYP2C9, elevating levels; contraindicated in active
bleed or pregnancy; mechanism: competitive antagonism of vitamin K epoxide
reductase.
5. Antidiabetics: Metformin is initiated for type 2 diabetes. What teaching
addresses a key contraindication?
A) Take with meals to prevent hypoglycemia B) Avoid in renal impairment (eGFR
<30) C) Monitor for weight gain D) Use alcohol freely B) Avoid in renal
impairment (eGFR <30) Rationale: Metformin decreases hepatic gluconeogenesis
and increases insulin sensitivity; lactic acidosis risk in renal failure due to
accumulation; interacts with iodinated contrast, requiring hold; no hypoglycemia
as it's non-hypoglycemic.
6. Antipsychotics: Risperidone for schizophrenia may cause extrapyramidal
symptoms. Mechanism?
A) Dopamine D2 blockade B) Serotonin 5-HT2A antagonism C) Alpha-1 blockade
D) Histamine H1 blockade A) Dopamine D2 blockade Rationale: Atypical
antipsychotics like risperidone block D2 receptors, reducing positive symptoms but
risking EPS; contraindicated in dementia-related psychosis (increased mortality);
interacts with antihypertensives, causing hypotension.
7. Beta-Blockers: Propranolol for migraine prophylaxis. Adverse effect from
mechanism?
A) Bronchospasm B) Tachycardia C) Hyperglycemia D) Diarrhea A)
Bronchospasm Rationale: Non-selective beta-blocker antagonizes beta-1/2
receptors, reducing heart rate and contractility; contraindicated in asthma/COPD;
interacts with calcium channel blockers, risking bradycardia/AV block.
8. Antivirals: Acyclovir for herpes zoster. Key interaction?
A) Probenecid increases nephrotoxicity B) Nephrotoxic drugs like
aminoglycosides C) Antacids decrease absorption D) Warfarin decreases efficacy
B) Nephrotoxic drugs like aminoglycosides Rationale: Acyclovir inhibits viral
, DNA polymerase; renal excretion, so additive nephrotoxicity with other renally
cleared drugs; contraindicated in severe renal impairment; hydrate to prevent
crystal nephropathy.
9. Diuretics: Furosemide IV for acute pulmonary edema. Mechanism?
A) Inhibits carbonic anhydrase B) Blocks Na/K/2Cl cotransporter C) Inhibits
aldosterone D) Increases uric acid reabsorption B) Blocks Na/K/2Cl cotransporter
Rationale: Loop diuretic inhibits NKCC2 in loop of Henle, promoting diuresis;
contraindicated in anuria; interacts with digoxin, risking toxicity from
hypokalemia/hypomagnesemia.
10. Statins: Atorvastatin for hyperlipidemia. Contraindication?
A) Active liver disease B) Hypothyroidism C) Renal stones D) Peptic ulcers A)
Active liver disease Rationale: HMG-CoA reductase inhibitor reduces cholesterol
synthesis; hepatotoxicity risk; interacts with fibrates/gemfibrozil, increasing
myopathy/rhabdomyolysis; monitor LFTs/AST/ALT.
11. Antiemetics: Ondansetron for chemotherapy-induced nausea.
Mechanism?
A) Dopamine D2 antagonist B) 5-HT3 receptor antagonist C) H1 antagonist D)
Muscarinic antagonist B) 5-HT3 receptor antagonist Rationale: Blocks serotonin
receptors in CTZ and GI tract; contraindicated in congenital long QT; interacts
with apomorphine, risking profound hypotension.
12. Bronchodilators: Albuterol MDI for asthma. Adverse effect?
A) Bradycardia B) Tremors C) Hypotension D) Sedation B) Tremors Rationale:
Beta-2 agonist relaxes bronchial smooth muscle; stimulates skeletal muscle beta-2
receptors; contraindicated in tachyarrhythmias; interacts with beta-blockers,
antagonizing effects.
13. Antidepressants: Fluoxetine for depression. Interaction with warfarin?
A) Decreases INR B) Increases INR C) No effect D) Causes serotonin syndrome
B) Increases INR Rationale: SSRI inhibits CYP2C9, elevating warfarin levels;
mechanism: serotonin reuptake inhibition; contraindicated with MAOIs (serotonin
syndrome); taper to avoid withdrawal.
Exam | 2025/2026 Verified
Questions & A+ Correct
Answers
1. Antibiotics: A client with a penicillin allergy is prescribed erythromycin for
streptococcal pharyngitis. What is the primary mechanism of action?
A) Inhibits cell wall synthesis B) Inhibits protein synthesis C) Disrupts DNA
replication D) Inhibits folic acid synthesis B) Inhibits protein synthesis Rationale:
Erythromycin, a macrolide, binds to the 50S ribosomal subunit, inhibiting
bacterial protein synthesis; contraindicated in clients with QT prolongation due to
risk of torsades de pointes; interacts with CYP3A4 inhibitors like ketoconazole,
increasing levels.
2. Antihypertensives: Lisinopril is prescribed for hypertension. The nurse
should monitor for which adverse effect due to its mechanism?
A) Hyperkalemia B) Hypoglycemia C) Bradycardia D) Constipation A)
Hyperkalemia Rationale: As an ACE inhibitor, lisinopril blocks angiotensin II
formation, reducing aldosterone and potassium excretion; contraindicated in
pregnancy (fetal renal damage); interacts with potassium-sparing diuretics,
exacerbating hyperkalemia.
3. Analgesics: A client post-op receives IV morphine. What is the primary
contraindication?
A) Renal impairment B) Respiratory depression C) Liver failure D)
Hypothyroidism B) Respiratory depression Rationale: Morphine, an opioid
agonist, binds mu-receptors, causing analgesia but suppressing respiration;
mechanism involves CNS depression; interacts with CNS depressants like
benzodiazepines, increasing overdose risk; monitor RR <12/min.
,4. Anticoagulants: Warfarin therapy requires monitoring of INR. What
interaction increases bleeding risk?
A) Vitamin K-rich foods B) Cranberry juice C) St. John's wort D) Grapefruit juice
B) Cranberry juice Rationale: Warfarin inhibits vitamin K-dependent clotting
factors; cranberry inhibits CYP2C9, elevating levels; contraindicated in active
bleed or pregnancy; mechanism: competitive antagonism of vitamin K epoxide
reductase.
5. Antidiabetics: Metformin is initiated for type 2 diabetes. What teaching
addresses a key contraindication?
A) Take with meals to prevent hypoglycemia B) Avoid in renal impairment (eGFR
<30) C) Monitor for weight gain D) Use alcohol freely B) Avoid in renal
impairment (eGFR <30) Rationale: Metformin decreases hepatic gluconeogenesis
and increases insulin sensitivity; lactic acidosis risk in renal failure due to
accumulation; interacts with iodinated contrast, requiring hold; no hypoglycemia
as it's non-hypoglycemic.
6. Antipsychotics: Risperidone for schizophrenia may cause extrapyramidal
symptoms. Mechanism?
A) Dopamine D2 blockade B) Serotonin 5-HT2A antagonism C) Alpha-1 blockade
D) Histamine H1 blockade A) Dopamine D2 blockade Rationale: Atypical
antipsychotics like risperidone block D2 receptors, reducing positive symptoms but
risking EPS; contraindicated in dementia-related psychosis (increased mortality);
interacts with antihypertensives, causing hypotension.
7. Beta-Blockers: Propranolol for migraine prophylaxis. Adverse effect from
mechanism?
A) Bronchospasm B) Tachycardia C) Hyperglycemia D) Diarrhea A)
Bronchospasm Rationale: Non-selective beta-blocker antagonizes beta-1/2
receptors, reducing heart rate and contractility; contraindicated in asthma/COPD;
interacts with calcium channel blockers, risking bradycardia/AV block.
8. Antivirals: Acyclovir for herpes zoster. Key interaction?
A) Probenecid increases nephrotoxicity B) Nephrotoxic drugs like
aminoglycosides C) Antacids decrease absorption D) Warfarin decreases efficacy
B) Nephrotoxic drugs like aminoglycosides Rationale: Acyclovir inhibits viral
, DNA polymerase; renal excretion, so additive nephrotoxicity with other renally
cleared drugs; contraindicated in severe renal impairment; hydrate to prevent
crystal nephropathy.
9. Diuretics: Furosemide IV for acute pulmonary edema. Mechanism?
A) Inhibits carbonic anhydrase B) Blocks Na/K/2Cl cotransporter C) Inhibits
aldosterone D) Increases uric acid reabsorption B) Blocks Na/K/2Cl cotransporter
Rationale: Loop diuretic inhibits NKCC2 in loop of Henle, promoting diuresis;
contraindicated in anuria; interacts with digoxin, risking toxicity from
hypokalemia/hypomagnesemia.
10. Statins: Atorvastatin for hyperlipidemia. Contraindication?
A) Active liver disease B) Hypothyroidism C) Renal stones D) Peptic ulcers A)
Active liver disease Rationale: HMG-CoA reductase inhibitor reduces cholesterol
synthesis; hepatotoxicity risk; interacts with fibrates/gemfibrozil, increasing
myopathy/rhabdomyolysis; monitor LFTs/AST/ALT.
11. Antiemetics: Ondansetron for chemotherapy-induced nausea.
Mechanism?
A) Dopamine D2 antagonist B) 5-HT3 receptor antagonist C) H1 antagonist D)
Muscarinic antagonist B) 5-HT3 receptor antagonist Rationale: Blocks serotonin
receptors in CTZ and GI tract; contraindicated in congenital long QT; interacts
with apomorphine, risking profound hypotension.
12. Bronchodilators: Albuterol MDI for asthma. Adverse effect?
A) Bradycardia B) Tremors C) Hypotension D) Sedation B) Tremors Rationale:
Beta-2 agonist relaxes bronchial smooth muscle; stimulates skeletal muscle beta-2
receptors; contraindicated in tachyarrhythmias; interacts with beta-blockers,
antagonizing effects.
13. Antidepressants: Fluoxetine for depression. Interaction with warfarin?
A) Decreases INR B) Increases INR C) No effect D) Causes serotonin syndrome
B) Increases INR Rationale: SSRI inhibits CYP2C9, elevating warfarin levels;
mechanism: serotonin reuptake inhibition; contraindicated with MAOIs (serotonin
syndrome); taper to avoid withdrawal.
