HOSA PHARMACOLOGY EXAM –LATEST EDITION |
200 ACTUAL EXAM QUESTIONS WITH CORRECT
DETAILED ANSWERS | A+ GRADED.
1. A 68-year-old patient with heart failure is prescribed digoxin 0.25 mg daily. Which laboratory value
requires immediate intervention before administration?
A. Sodium 138 mEq/L
B. Potassium 2.8 mEq/L
C. Glucose 110 mg/dL
D. Creatinine 1.2 mg/dL
Answer: B
Rationale: Hypokalemia (K+ <3.5 mEq/L) significantly increases the risk of digoxin toxicity by
enhancing digoxin's binding to the Na+/K+ ATPase pump. Digoxin toxicity can lead to life-threatening
arrhythmias. Normal potassium ranges from 3.5-5.0 mEq/L. The other values are within normal limits
or not immediately concerning for digoxin administration.
2. A patient receiving morphine PCA post-operatively develops respiratory depression. Which
medication should the nurse prepare to administer?
A. Naloxone
B. Flumazenil
C. Naltrexone
D. Methadone
Answer: A
Rationale: Naloxone is an opioid antagonist that competitively blocks mu-opioid receptors, rapidly
reversing opioid-induced respiratory depression. It has an onset of 1-2 minutes when given IV.
Flumazenil reverses benzodiazepines, naltrexone is for opioid/alcohol dependence (not acute
reversal), and methadone is another opioid that would worsen respiratory depression.
3. A 55-year-old with atrial fibrillation is started on warfarin. The target INR range is:
A. 0.8-1.2
B. 1.5-2.0
C. 2.0-3.0
D. 3.0-4.0
Answer: C
,Rationale: For atrial fibrillation, the therapeutic INR range is 2.0-3.0, which provides adequate
anticoagulation to prevent stroke while minimizing bleeding risk. An INR of 0.8-1.2 is normal (not
anticoagulated), 1.5-2.0 is subtherapeutic, and 3.0-4.0 is reserved for high-risk conditions like
mechanical heart valves.
4. Which antibiotic requires peak and trough levels to be drawn to prevent nephrotoxicity and
ototoxicity?
A. Azithromycin
B. Gentamicin
C. Amoxicillin
D. Cephalexin
Answer: B
Rationale: Gentamicin is an aminoglycoside with a narrow therapeutic index that can cause
nephrotoxicity and irreversible ototoxicity. Peak levels (drawn 30 minutes after infusion) ensure
therapeutic efficacy, while trough levels (drawn immediately before next dose) prevent toxicity. The
other antibiotics do not require routine serum level monitoring.
5. A patient taking phenytoin presents with nystagmus, ataxia, and confusion. The nurse suspects
toxicity. Which intervention is priority?
A. Administer vitamin D supplementation
B. Check serum phenytoin level
C. Increase the dose for breakthrough seizures
D. Switch to immediate-release formulation
Answer: B
Rationale: These are classic signs of phenytoin toxicity (therapeutic range: 10-20 mcg/mL). Checking
the serum level confirms toxicity and guides treatment. Nystagmus appears first at levels >20 mcg/mL,
followed by ataxia and cognitive changes. Administering vitamin D or increasing the dose would be
harmful, and formulation change wouldn't address toxicity.
6. A 45-year-old diabetic is prescribed metformin. Which condition is an absolute contraindication for
metformin use?
A. Heart failure
B. Chronic kidney disease with eGFR 25 mL/min/1.73m²
C. Hypertension
D. Age >80 years
Answer: B
,Rationale: Metformin is contraindicated when eGFR <30 mL/min/1.73m² due to increased risk of lactic
acidosis, a rare but potentially fatal complication. Metformin is excreted unchanged by the kidneys.
While caution is advised in heart failure and elderly patients, these are not absolute contraindications
if kidney function is adequate.
7. A patient receiving heparin infusion develops thrombocytopenia. Which test confirms heparin-
induced thrombocytopenia (HIT)?
A. PT/INR
B. Anti-factor Xa assay
C. Serotonin release assay
D. Bleeding time
Answer: C
Rationale: The serotonin release assay is the gold standard for diagnosing HIT, with high sensitivity
and specificity. It measures antibody-mediated platelet activation in the presence of heparin. PT/INR
monitors warfarin, anti-factor Xa assays heparin levels, and bleeding time is nonspecific. HIT requires
immediate heparin discontinuation.
8. Calculate the flow rate for D5W 1000 mL to infuse over 8 hours using a 15 gtt/mL administration
set.
A. 15 gtt/min
B. 21 gtt/min
C. 31 gtt/min
D. 45 gtt/min
Answer: C
Rationale: Using the formula: (Total volume × Drop factor) ÷ Time in minutes = (1000 mL × 15 gtt/mL)
÷ (8 × 60 minutes) = 15,000 ÷ 480 = 31.25 gtt/min, rounded to 31 gtt/min. This ensures the entire 1000
mL infuses evenly over 8 hours.
9. A patient is prescribed levothyroxine 150 mcg daily. Which instruction is most important?
A. "Take with breakfast to prevent stomach upset."
B. "Take on an empty stomach 30-60 minutes before breakfast."
C. "Take at bedtime with a snack."
D. "Take with calcium supplements for better absorption."
Answer: B
Rationale: Levothyroxine absorption is significantly reduced (by up to 55%) when taken with food,
especially calcium, iron, and fiber. Taking it on an empty stomach 30-60 minutes before breakfast
, ensures optimal and consistent absorption. Food, calcium, and timing with meals all interfere with
thyroid hormone replacement.
10. A patient taking isoniazid for TB prophylaxis should be instructed to avoid which food?
A. Dairy products
B. Grapefruit juice
C. Aged cheese
D. Leafy green vegetables
Answer: C
Rationale: Isoniazid inhibits monoamine oxidase, leading to tyramine accumulation when consumed
with tyramine-rich foods like aged cheese, wine, and processed meats. This can cause hypertensive
crisis. The other foods do not interact with isoniazid. Patients should be taught about MAO-inhibitor
dietary restrictions.
11. Which beta-blocker is MOST cardioselective at low doses?
A. Propranolol
B. Nadolol
C. Atenolol
D. Carvedilol
Answer: C
Rationale: Atenolol is a beta-1 selective (cardioselective) blocker at low doses (<100 mg), primarily
affecting cardiac beta-1 receptors rather than bronchial beta-2 receptors. This makes it safer in
patients with respiratory conditions. Propranolol and nadolol are non-selective, while carvedilol
blocks both beta and alpha receptors.
12. A patient receiving chemotherapy has a WBC count of 1800/mm³. Which medication stimulates
white blood cell production?
A. Epoetin alfa
B. Filgrastim
C. Oprelvekin
D. Romiplostim
Answer: B
Rationale: Filgrastim (G-CSF) stimulates neutrophil production and is used to prevent febrile
neutropenia in chemotherapy patients. Epoetin alfa stimulates red blood cell production, oprelvekin
stimulates platelets, and romiplostim is for chronic immune thrombocytopenia. WBC <2000/mm³
indicates severe neutropenia requiring intervention.
200 ACTUAL EXAM QUESTIONS WITH CORRECT
DETAILED ANSWERS | A+ GRADED.
1. A 68-year-old patient with heart failure is prescribed digoxin 0.25 mg daily. Which laboratory value
requires immediate intervention before administration?
A. Sodium 138 mEq/L
B. Potassium 2.8 mEq/L
C. Glucose 110 mg/dL
D. Creatinine 1.2 mg/dL
Answer: B
Rationale: Hypokalemia (K+ <3.5 mEq/L) significantly increases the risk of digoxin toxicity by
enhancing digoxin's binding to the Na+/K+ ATPase pump. Digoxin toxicity can lead to life-threatening
arrhythmias. Normal potassium ranges from 3.5-5.0 mEq/L. The other values are within normal limits
or not immediately concerning for digoxin administration.
2. A patient receiving morphine PCA post-operatively develops respiratory depression. Which
medication should the nurse prepare to administer?
A. Naloxone
B. Flumazenil
C. Naltrexone
D. Methadone
Answer: A
Rationale: Naloxone is an opioid antagonist that competitively blocks mu-opioid receptors, rapidly
reversing opioid-induced respiratory depression. It has an onset of 1-2 minutes when given IV.
Flumazenil reverses benzodiazepines, naltrexone is for opioid/alcohol dependence (not acute
reversal), and methadone is another opioid that would worsen respiratory depression.
3. A 55-year-old with atrial fibrillation is started on warfarin. The target INR range is:
A. 0.8-1.2
B. 1.5-2.0
C. 2.0-3.0
D. 3.0-4.0
Answer: C
,Rationale: For atrial fibrillation, the therapeutic INR range is 2.0-3.0, which provides adequate
anticoagulation to prevent stroke while minimizing bleeding risk. An INR of 0.8-1.2 is normal (not
anticoagulated), 1.5-2.0 is subtherapeutic, and 3.0-4.0 is reserved for high-risk conditions like
mechanical heart valves.
4. Which antibiotic requires peak and trough levels to be drawn to prevent nephrotoxicity and
ototoxicity?
A. Azithromycin
B. Gentamicin
C. Amoxicillin
D. Cephalexin
Answer: B
Rationale: Gentamicin is an aminoglycoside with a narrow therapeutic index that can cause
nephrotoxicity and irreversible ototoxicity. Peak levels (drawn 30 minutes after infusion) ensure
therapeutic efficacy, while trough levels (drawn immediately before next dose) prevent toxicity. The
other antibiotics do not require routine serum level monitoring.
5. A patient taking phenytoin presents with nystagmus, ataxia, and confusion. The nurse suspects
toxicity. Which intervention is priority?
A. Administer vitamin D supplementation
B. Check serum phenytoin level
C. Increase the dose for breakthrough seizures
D. Switch to immediate-release formulation
Answer: B
Rationale: These are classic signs of phenytoin toxicity (therapeutic range: 10-20 mcg/mL). Checking
the serum level confirms toxicity and guides treatment. Nystagmus appears first at levels >20 mcg/mL,
followed by ataxia and cognitive changes. Administering vitamin D or increasing the dose would be
harmful, and formulation change wouldn't address toxicity.
6. A 45-year-old diabetic is prescribed metformin. Which condition is an absolute contraindication for
metformin use?
A. Heart failure
B. Chronic kidney disease with eGFR 25 mL/min/1.73m²
C. Hypertension
D. Age >80 years
Answer: B
,Rationale: Metformin is contraindicated when eGFR <30 mL/min/1.73m² due to increased risk of lactic
acidosis, a rare but potentially fatal complication. Metformin is excreted unchanged by the kidneys.
While caution is advised in heart failure and elderly patients, these are not absolute contraindications
if kidney function is adequate.
7. A patient receiving heparin infusion develops thrombocytopenia. Which test confirms heparin-
induced thrombocytopenia (HIT)?
A. PT/INR
B. Anti-factor Xa assay
C. Serotonin release assay
D. Bleeding time
Answer: C
Rationale: The serotonin release assay is the gold standard for diagnosing HIT, with high sensitivity
and specificity. It measures antibody-mediated platelet activation in the presence of heparin. PT/INR
monitors warfarin, anti-factor Xa assays heparin levels, and bleeding time is nonspecific. HIT requires
immediate heparin discontinuation.
8. Calculate the flow rate for D5W 1000 mL to infuse over 8 hours using a 15 gtt/mL administration
set.
A. 15 gtt/min
B. 21 gtt/min
C. 31 gtt/min
D. 45 gtt/min
Answer: C
Rationale: Using the formula: (Total volume × Drop factor) ÷ Time in minutes = (1000 mL × 15 gtt/mL)
÷ (8 × 60 minutes) = 15,000 ÷ 480 = 31.25 gtt/min, rounded to 31 gtt/min. This ensures the entire 1000
mL infuses evenly over 8 hours.
9. A patient is prescribed levothyroxine 150 mcg daily. Which instruction is most important?
A. "Take with breakfast to prevent stomach upset."
B. "Take on an empty stomach 30-60 minutes before breakfast."
C. "Take at bedtime with a snack."
D. "Take with calcium supplements for better absorption."
Answer: B
Rationale: Levothyroxine absorption is significantly reduced (by up to 55%) when taken with food,
especially calcium, iron, and fiber. Taking it on an empty stomach 30-60 minutes before breakfast
, ensures optimal and consistent absorption. Food, calcium, and timing with meals all interfere with
thyroid hormone replacement.
10. A patient taking isoniazid for TB prophylaxis should be instructed to avoid which food?
A. Dairy products
B. Grapefruit juice
C. Aged cheese
D. Leafy green vegetables
Answer: C
Rationale: Isoniazid inhibits monoamine oxidase, leading to tyramine accumulation when consumed
with tyramine-rich foods like aged cheese, wine, and processed meats. This can cause hypertensive
crisis. The other foods do not interact with isoniazid. Patients should be taught about MAO-inhibitor
dietary restrictions.
11. Which beta-blocker is MOST cardioselective at low doses?
A. Propranolol
B. Nadolol
C. Atenolol
D. Carvedilol
Answer: C
Rationale: Atenolol is a beta-1 selective (cardioselective) blocker at low doses (<100 mg), primarily
affecting cardiac beta-1 receptors rather than bronchial beta-2 receptors. This makes it safer in
patients with respiratory conditions. Propranolol and nadolol are non-selective, while carvedilol
blocks both beta and alpha receptors.
12. A patient receiving chemotherapy has a WBC count of 1800/mm³. Which medication stimulates
white blood cell production?
A. Epoetin alfa
B. Filgrastim
C. Oprelvekin
D. Romiplostim
Answer: B
Rationale: Filgrastim (G-CSF) stimulates neutrophil production and is used to prevent febrile
neutropenia in chemotherapy patients. Epoetin alfa stimulates red blood cell production, oprelvekin
stimulates platelets, and romiplostim is for chronic immune thrombocytopenia. WBC <2000/mm³
indicates severe neutropenia requiring intervention.
