ATI Pharmacology CMS Proctored Exam
(NGN) 2026 | Actual Exam Practice
Questions & Verified Answers with Detailed
Rationales | Complete RN Pharmacology
Review PDF
• This material contains 200 practice questions modeled after the ATI Pharmacology
CMS Proctored Exam (NGN) 2026, featuring verified answers, detailed EXPERT
RATIONALE, and full RN pharmacology topic coverage.
• Study by reading each question carefully, selecting your answer before revealing
the correct option, then reviewing the EXPERT RATIONALE to reinforce
understanding of drug mechanisms, nursing priorities, and client safety.
1. A nurse is preparing to administer metoprolol to a client. Which assessment
finding should prompt the nurse to withhold the medication and notify the
provider?
A. Blood pressure of 138/88 mmHg
B. Heart rate of 58 beats per minute
C. Respiratory rate of 16 breaths per minute
D. Oxygen saturation of 97%
E. Temperature of 37.1°C
Correct Answer: B. Heart rate of 58 beats per minute
EXPERT RATIONALE: Metoprolol is a beta-1 selective blocker that decreases heart
rate and blood pressure. A heart rate below 60 bpm indicates bradycardia, which is
a contraindication for administration. The nurse should withhold the drug and
notify the provider immediately to prevent further cardiac depression.
2. A client is prescribed warfarin therapy. Which laboratory value is the
priority for the nurse to monitor?
A. Complete blood count (CBC)
,B. Serum potassium level
C. International Normalized Ratio (INR)
D. Serum creatinine level
E. Platelet count
Correct Answer: C. International Normalized Ratio (INR)
EXPERT RATIONALE: Warfarin is an anticoagulant that works by inhibiting vitamin
K-dependent clotting factors. The INR is the gold standard for monitoring warfarin
therapy. A therapeutic INR for most indications is 2.0–3.0. Values above this range
increase bleeding risk; values below indicate subtherapeutic anticoagulation.
3. A nurse is teaching a client about taking oral iron supplements. Which
instruction is most important?
A. Take iron with milk to reduce GI upset
B. Expect stools to turn bright red during therapy
C. Take iron with a glass of orange juice on an empty stomach
D. Avoid all physical activity while taking iron
E. Take iron with antacids to improve absorption
Correct Answer: C. Take iron with a glass of orange juice on an empty
stomach
EXPERT RATIONALE: Vitamin C (ascorbic acid) in orange juice enhances iron
absorption by converting ferric iron to the more absorbable ferrous form. Iron is
best absorbed on an empty stomach. Milk, antacids, and calcium inhibit absorption.
Stools will turn dark/tarry, not bright red.
4. A client receiving heparin therapy develops sudden onset of low platelet
count on day 8 of therapy. What condition should the nurse suspect?
A. Disseminated intravascular coagulation (DIC)
,B. Heparin-induced thrombocytopenia (HIT)
C. Idiopathic thrombocytopenic purpura (ITP)
D. Vitamin K deficiency
E. Hemophilia A exacerbation
Correct Answer: B. Heparin-induced thrombocytopenia (HIT)
EXPERT RATIONALE: HIT is an immune-mediated adverse reaction to heparin that
typically occurs 5–10 days after initiation. It is characterized by a drop in platelet
count of more than 50% from baseline. Paradoxically, HIT causes thrombosis, not
bleeding. Heparin must be discontinued immediately and an alternative
anticoagulant initiated.
5. A nurse is caring for a client prescribed lithium for bipolar disorder. Which
symptom indicates lithium toxicity?
A. Increased thirst and urination
B. Fine hand tremors
C. Coarse tremors, confusion, and ataxia
D. Mild nausea when initiating therapy
E. Weight gain of 1 kg over one month
Correct Answer: C. Coarse tremors, confusion, and ataxia
EXPERT RATIONALE: Early lithium side effects include fine tremors, polyuria, and
mild nausea. Toxicity (serum level >1.5 mEq/L) manifests as coarse tremors,
confusion, ataxia, seizures, and cardiac dysrhythmias. Lithium has a narrow
therapeutic index (0.6–1.2 mEq/L), and levels must be monitored regularly.
6. A nurse is preparing to administer digoxin to a client with heart failure.
Which assessment finding requires the nurse to withhold the dose?
A. Apical pulse of 68 bpm
, B. Blood pressure of 110/70 mmHg
C. Serum potassium of 3.1 mEq/L
D. Respiratory rate of 18 breaths per minute
E. Weight gain of 0.5 kg since yesterday
Correct Answer: C. Serum potassium of 3.1 mEq/L
EXPERT RATIONALE: Hypokalemia (K⁺ < 3.5 mEq/L) potentiates digoxin toxicity by
increasing the drug's binding to cardiac cells, leading to life-threatening
dysrhythmias. The nurse should withhold digoxin and report the potassium level to
the provider before administration.
7. A client is prescribed metformin for type 2 diabetes. Which condition is an
absolute contraindication to this medication?
A. Obesity
B. Hypertension
C. Renal impairment (GFR < 30 mL/min)
D. Hyperlipidemia
E. Peripheral neuropathy
Correct Answer: C. Renal impairment (GFR < 30 mL/min)
EXPERT RATIONALE: Metformin is contraindicated in renal impairment because
the kidneys clear it from the body. Impaired clearance leads to metformin
accumulation and the risk of lactic acidosis, a rare but potentially fatal complication.
GFR should be assessed before initiating therapy and monitored periodically.
8. A nurse is educating a client about atorvastatin. Which instruction should
be included?
A. Take the medication in the morning with food
(NGN) 2026 | Actual Exam Practice
Questions & Verified Answers with Detailed
Rationales | Complete RN Pharmacology
Review PDF
• This material contains 200 practice questions modeled after the ATI Pharmacology
CMS Proctored Exam (NGN) 2026, featuring verified answers, detailed EXPERT
RATIONALE, and full RN pharmacology topic coverage.
• Study by reading each question carefully, selecting your answer before revealing
the correct option, then reviewing the EXPERT RATIONALE to reinforce
understanding of drug mechanisms, nursing priorities, and client safety.
1. A nurse is preparing to administer metoprolol to a client. Which assessment
finding should prompt the nurse to withhold the medication and notify the
provider?
A. Blood pressure of 138/88 mmHg
B. Heart rate of 58 beats per minute
C. Respiratory rate of 16 breaths per minute
D. Oxygen saturation of 97%
E. Temperature of 37.1°C
Correct Answer: B. Heart rate of 58 beats per minute
EXPERT RATIONALE: Metoprolol is a beta-1 selective blocker that decreases heart
rate and blood pressure. A heart rate below 60 bpm indicates bradycardia, which is
a contraindication for administration. The nurse should withhold the drug and
notify the provider immediately to prevent further cardiac depression.
2. A client is prescribed warfarin therapy. Which laboratory value is the
priority for the nurse to monitor?
A. Complete blood count (CBC)
,B. Serum potassium level
C. International Normalized Ratio (INR)
D. Serum creatinine level
E. Platelet count
Correct Answer: C. International Normalized Ratio (INR)
EXPERT RATIONALE: Warfarin is an anticoagulant that works by inhibiting vitamin
K-dependent clotting factors. The INR is the gold standard for monitoring warfarin
therapy. A therapeutic INR for most indications is 2.0–3.0. Values above this range
increase bleeding risk; values below indicate subtherapeutic anticoagulation.
3. A nurse is teaching a client about taking oral iron supplements. Which
instruction is most important?
A. Take iron with milk to reduce GI upset
B. Expect stools to turn bright red during therapy
C. Take iron with a glass of orange juice on an empty stomach
D. Avoid all physical activity while taking iron
E. Take iron with antacids to improve absorption
Correct Answer: C. Take iron with a glass of orange juice on an empty
stomach
EXPERT RATIONALE: Vitamin C (ascorbic acid) in orange juice enhances iron
absorption by converting ferric iron to the more absorbable ferrous form. Iron is
best absorbed on an empty stomach. Milk, antacids, and calcium inhibit absorption.
Stools will turn dark/tarry, not bright red.
4. A client receiving heparin therapy develops sudden onset of low platelet
count on day 8 of therapy. What condition should the nurse suspect?
A. Disseminated intravascular coagulation (DIC)
,B. Heparin-induced thrombocytopenia (HIT)
C. Idiopathic thrombocytopenic purpura (ITP)
D. Vitamin K deficiency
E. Hemophilia A exacerbation
Correct Answer: B. Heparin-induced thrombocytopenia (HIT)
EXPERT RATIONALE: HIT is an immune-mediated adverse reaction to heparin that
typically occurs 5–10 days after initiation. It is characterized by a drop in platelet
count of more than 50% from baseline. Paradoxically, HIT causes thrombosis, not
bleeding. Heparin must be discontinued immediately and an alternative
anticoagulant initiated.
5. A nurse is caring for a client prescribed lithium for bipolar disorder. Which
symptom indicates lithium toxicity?
A. Increased thirst and urination
B. Fine hand tremors
C. Coarse tremors, confusion, and ataxia
D. Mild nausea when initiating therapy
E. Weight gain of 1 kg over one month
Correct Answer: C. Coarse tremors, confusion, and ataxia
EXPERT RATIONALE: Early lithium side effects include fine tremors, polyuria, and
mild nausea. Toxicity (serum level >1.5 mEq/L) manifests as coarse tremors,
confusion, ataxia, seizures, and cardiac dysrhythmias. Lithium has a narrow
therapeutic index (0.6–1.2 mEq/L), and levels must be monitored regularly.
6. A nurse is preparing to administer digoxin to a client with heart failure.
Which assessment finding requires the nurse to withhold the dose?
A. Apical pulse of 68 bpm
, B. Blood pressure of 110/70 mmHg
C. Serum potassium of 3.1 mEq/L
D. Respiratory rate of 18 breaths per minute
E. Weight gain of 0.5 kg since yesterday
Correct Answer: C. Serum potassium of 3.1 mEq/L
EXPERT RATIONALE: Hypokalemia (K⁺ < 3.5 mEq/L) potentiates digoxin toxicity by
increasing the drug's binding to cardiac cells, leading to life-threatening
dysrhythmias. The nurse should withhold digoxin and report the potassium level to
the provider before administration.
7. A client is prescribed metformin for type 2 diabetes. Which condition is an
absolute contraindication to this medication?
A. Obesity
B. Hypertension
C. Renal impairment (GFR < 30 mL/min)
D. Hyperlipidemia
E. Peripheral neuropathy
Correct Answer: C. Renal impairment (GFR < 30 mL/min)
EXPERT RATIONALE: Metformin is contraindicated in renal impairment because
the kidneys clear it from the body. Impaired clearance leads to metformin
accumulation and the risk of lactic acidosis, a rare but potentially fatal complication.
GFR should be assessed before initiating therapy and monitored periodically.
8. A nurse is educating a client about atorvastatin. Which instruction should
be included?
A. Take the medication in the morning with food
