NURS 251 Pharmacology Final Exam
Portage Learning Review ACTUAL
EXAM 2026/2027 | Portage NURS 251
Pharm | Verified Q&A | Pass
Guaranteed - A+ Graded
MODULE 1: Pharmacokinetics & Pharmacodynamics (15 Questions)
Q1: A drug with high first-pass effect is administered orally. What adjustment is MOST likely required?
A. Reduce the dose to avoid toxicity.
B. Increase the dose or choose a different route. [CORRECT]
C. Administer with food to enhance absorption.
D. Add a CYP450 inhibitor to slow metabolism.
Correct Answer: B Rationale: First-pass effect refers to extensive hepatic metabolism of an oral drug
before reaching systemic circulation, significantly reducing bioavailability. Increasing the dose
compensates for this loss, or switching to IV/sublingual/buccal routes bypasses the liver entirely. A is
incorrect because high first-pass reduces, not increases, systemic drug levels. C may help absorption for
some drugs but does not address hepatic metabolism. D is unsafe without specific indication and could
cause dangerous toxicity by non-selectively inhibiting drug metabolism.
Q2: [CALCULATION] Order: Heparin 800 units/hour IV. Available: Heparin 25,000 units in 500 mL D5W.
What is the flow rate in mL/hr?
A. 8 mL/hr
B. 12 mL/hr
C. 16 mL/hr [CORRECT]
, D. 20 mL/hr
Correct Answer: C Rationale: Concentration = 25,000 units ÷ 500 mL = 50 units/mL. Desired 800 units/hr
÷ 50 units/mL = 16 mL/hr. A (8 mL/hr) incorrectly uses 100 units/mL concentration. B (12 mL/hr)
miscalculates concentration as ~66.7 units/mL. D (20 mL/hr) inverts the ratio or uses incorrect formula.
Formula: (Desired Dose ÷ Available Concentration) = Flow Rate.
Q3: A patient taking warfarin is prescribed a new antibiotic. The nurse recognizes that antibiotics
increase warfarin levels through which mechanism?
A. Increased renal excretion of warfarin
B. Inhibition of CYP2C9 hepatic metabolism [CORRECT]
C. Enhanced plasma protein binding
D. Induction of P-glycoprotein efflux pumps
Correct Answer: B Rationale: Many antibiotics (especially macrolides, metronidazole, trimethoprim-
sulfamethoxazole) inhibit CYP2C9, the primary enzyme metabolizing S-warfarin (the more potent
isomer). This inhibition reduces warfarin clearance, increasing INR and bleeding risk. A is incorrect
because antibiotics do not increase renal excretion of warfarin. C is incorrect because antibiotics
typically displace warfarin from protein binding sites or inhibit metabolism, not enhance binding. D is
incorrect because P-glycoprotein induction would reduce absorption, not increase levels.
Q4: [CALCULATION] A pediatric patient weighs 22 lbs. The physician orders Amoxicillin 20 mg/kg/day
divided BID. How many mg should the nurse administer per dose?
A. 50 mg
B. 100 mg [CORRECT]
C. 200 mg
D. 400 mg
Correct Answer: B Rationale: First convert weight: 22 lbs ÷ 2.2 = 10 kg. Total daily dose = 20 mg/kg/day
× 10 kg = 200 mg/day. Divided BID (twice daily) = 200 mg ÷ 2 = 100 mg per dose. A (50 mg) incorrectly
divides by 4. C (200 mg) gives total daily dose, not per-dose. D (400 mg) doubles the total daily dose.
Formula: (Weight in kg × Dose per kg) ÷ Number of doses.
Q5: Which factor would INCREASE the volume of distribution (Vd) of a lipophilic drug?
, A. Increased patient age with decreased body fat
B. Third-spacing due to ascites or edema
C. Increased adipose tissue percentage [CORRECT]
D. Decreased plasma protein binding
Correct Answer: C Rationale: Lipophilic drugs distribute extensively into adipose tissue. Increased body
fat creates a larger reservoir for the drug, increasing Vd and potentially prolonging half-life. A is
incorrect because decreased body fat reduces distribution into lipid compartments. B is incorrect
because third-spacing affects hydrophilic drugs, not lipophilic ones. D is incorrect because decreased
protein binding increases free drug but does not significantly alter Vd for lipophilic drugs; Vd is
determined by tissue distribution, not plasma binding.
Q6: A patient on a beta-blocker develops bronchospasm. The nurse understands this adverse effect
occurs because beta-blockers:
A. Stimulate beta-2 receptors causing bronchodilation
B. Block beta-1 receptors in cardiac tissue only
C. Non-selectively block beta-2 receptors in bronchial smooth muscle [CORRECT]
D. Increase acetylcholine release at muscarinic receptors
Correct Answer: C Rationale: Non-selective beta-blockers (e.g., propranolol, nadolol) block both beta-1
(cardiac) and beta-2 (bronchial/pulmonary/vascular) receptors. Beta-2 receptor activation normally
causes bronchial smooth muscle relaxation; blocking these receptors causes bronchoconstriction and
can precipitate asthma attacks. A describes beta-2 agonist action (opposite effect). B describes
cardioselective beta-blockers (e.g., metoprolol, atenolol) which have less bronchial effect. D describes
cholinergic mechanism, unrelated to beta-blocker pharmacology.
Q7: [CALCULATION] Order: Digoxin 0.125 mg PO daily. Available: Digoxin 0.25 mg tablets. How many
tablets should the nurse administer?
A. 0.25 tablet
B. 0.5 tablet [CORRECT]
C. 1 tablet
D. 2 tablets
, Correct Answer: B Rationale: Desired dose (0.125 mg) ÷ Available dose per tablet (0.25 mg) = 0.5 tablet.
A (0.25 tablet) incorrectly divides 0.125 by 0.5. C (1 tablet) gives full available dose, which is double the
ordered dose and could cause toxicity. D (2 tablets) is a dangerous overdose. Always verify: 0.5 tablet ×
0.25 mg = 0.125 mg ordered dose.
Q8: Which statement BEST describes the therapeutic index (TI) of a drug?
A. The ratio between the effective dose and the toxic dose
B. The margin of safety between the median effective dose (ED50) and median lethal dose
(LD50) [CORRECT]
C. The time required to reach steady-state plasma concentration
D. The degree of receptor binding affinity
Correct Answer: B Rationale: Therapeutic index = LD50/ED50, representing the margin of safety
between the dose that helps 50% of the population and the dose that kills 50% of the population. A low
TI (e.g., digoxin, lithium, warfarin, aminoglycosides) indicates a narrow safety margin requiring careful
monitoring. A is incorrect because it does not specify median doses or lethal vs. effective. C describes
time to steady-state (approximately 5 half-lives). D describes receptor affinity (Kd), unrelated to safety
margin.
Q9: [CALCULATION] A patient requires 1.5 grams of Cefazolin IV. The vial contains 2 grams in 10 mL.
How many mL should the nurse withdraw?
A. 5.5 mL
B. 6.5 mL
C. 7.5 mL [CORRECT]
D. 8.5 mL
Correct Answer: C Rationale: Concentration = 2 grams ÷ 10 mL = 0.2 g/mL (200 mg/mL). 1.5 grams ÷ 0.2
g/mL = 7.5 mL. A (5.5 mL) underestimates by 2 mL. B (6.5 mL) uses incorrect concentration calculation. D
(8.5 mL) overestimates. Formula: Desired Dose ÷ (Total Drug ÷ Total Volume) = Volume to withdraw.
Q10: A drug with a half-life of 6 hours is started. Approximately how long will it take to reach steady-
state plasma concentration?
A. 6 hours
Portage Learning Review ACTUAL
EXAM 2026/2027 | Portage NURS 251
Pharm | Verified Q&A | Pass
Guaranteed - A+ Graded
MODULE 1: Pharmacokinetics & Pharmacodynamics (15 Questions)
Q1: A drug with high first-pass effect is administered orally. What adjustment is MOST likely required?
A. Reduce the dose to avoid toxicity.
B. Increase the dose or choose a different route. [CORRECT]
C. Administer with food to enhance absorption.
D. Add a CYP450 inhibitor to slow metabolism.
Correct Answer: B Rationale: First-pass effect refers to extensive hepatic metabolism of an oral drug
before reaching systemic circulation, significantly reducing bioavailability. Increasing the dose
compensates for this loss, or switching to IV/sublingual/buccal routes bypasses the liver entirely. A is
incorrect because high first-pass reduces, not increases, systemic drug levels. C may help absorption for
some drugs but does not address hepatic metabolism. D is unsafe without specific indication and could
cause dangerous toxicity by non-selectively inhibiting drug metabolism.
Q2: [CALCULATION] Order: Heparin 800 units/hour IV. Available: Heparin 25,000 units in 500 mL D5W.
What is the flow rate in mL/hr?
A. 8 mL/hr
B. 12 mL/hr
C. 16 mL/hr [CORRECT]
, D. 20 mL/hr
Correct Answer: C Rationale: Concentration = 25,000 units ÷ 500 mL = 50 units/mL. Desired 800 units/hr
÷ 50 units/mL = 16 mL/hr. A (8 mL/hr) incorrectly uses 100 units/mL concentration. B (12 mL/hr)
miscalculates concentration as ~66.7 units/mL. D (20 mL/hr) inverts the ratio or uses incorrect formula.
Formula: (Desired Dose ÷ Available Concentration) = Flow Rate.
Q3: A patient taking warfarin is prescribed a new antibiotic. The nurse recognizes that antibiotics
increase warfarin levels through which mechanism?
A. Increased renal excretion of warfarin
B. Inhibition of CYP2C9 hepatic metabolism [CORRECT]
C. Enhanced plasma protein binding
D. Induction of P-glycoprotein efflux pumps
Correct Answer: B Rationale: Many antibiotics (especially macrolides, metronidazole, trimethoprim-
sulfamethoxazole) inhibit CYP2C9, the primary enzyme metabolizing S-warfarin (the more potent
isomer). This inhibition reduces warfarin clearance, increasing INR and bleeding risk. A is incorrect
because antibiotics do not increase renal excretion of warfarin. C is incorrect because antibiotics
typically displace warfarin from protein binding sites or inhibit metabolism, not enhance binding. D is
incorrect because P-glycoprotein induction would reduce absorption, not increase levels.
Q4: [CALCULATION] A pediatric patient weighs 22 lbs. The physician orders Amoxicillin 20 mg/kg/day
divided BID. How many mg should the nurse administer per dose?
A. 50 mg
B. 100 mg [CORRECT]
C. 200 mg
D. 400 mg
Correct Answer: B Rationale: First convert weight: 22 lbs ÷ 2.2 = 10 kg. Total daily dose = 20 mg/kg/day
× 10 kg = 200 mg/day. Divided BID (twice daily) = 200 mg ÷ 2 = 100 mg per dose. A (50 mg) incorrectly
divides by 4. C (200 mg) gives total daily dose, not per-dose. D (400 mg) doubles the total daily dose.
Formula: (Weight in kg × Dose per kg) ÷ Number of doses.
Q5: Which factor would INCREASE the volume of distribution (Vd) of a lipophilic drug?
, A. Increased patient age with decreased body fat
B. Third-spacing due to ascites or edema
C. Increased adipose tissue percentage [CORRECT]
D. Decreased plasma protein binding
Correct Answer: C Rationale: Lipophilic drugs distribute extensively into adipose tissue. Increased body
fat creates a larger reservoir for the drug, increasing Vd and potentially prolonging half-life. A is
incorrect because decreased body fat reduces distribution into lipid compartments. B is incorrect
because third-spacing affects hydrophilic drugs, not lipophilic ones. D is incorrect because decreased
protein binding increases free drug but does not significantly alter Vd for lipophilic drugs; Vd is
determined by tissue distribution, not plasma binding.
Q6: A patient on a beta-blocker develops bronchospasm. The nurse understands this adverse effect
occurs because beta-blockers:
A. Stimulate beta-2 receptors causing bronchodilation
B. Block beta-1 receptors in cardiac tissue only
C. Non-selectively block beta-2 receptors in bronchial smooth muscle [CORRECT]
D. Increase acetylcholine release at muscarinic receptors
Correct Answer: C Rationale: Non-selective beta-blockers (e.g., propranolol, nadolol) block both beta-1
(cardiac) and beta-2 (bronchial/pulmonary/vascular) receptors. Beta-2 receptor activation normally
causes bronchial smooth muscle relaxation; blocking these receptors causes bronchoconstriction and
can precipitate asthma attacks. A describes beta-2 agonist action (opposite effect). B describes
cardioselective beta-blockers (e.g., metoprolol, atenolol) which have less bronchial effect. D describes
cholinergic mechanism, unrelated to beta-blocker pharmacology.
Q7: [CALCULATION] Order: Digoxin 0.125 mg PO daily. Available: Digoxin 0.25 mg tablets. How many
tablets should the nurse administer?
A. 0.25 tablet
B. 0.5 tablet [CORRECT]
C. 1 tablet
D. 2 tablets
, Correct Answer: B Rationale: Desired dose (0.125 mg) ÷ Available dose per tablet (0.25 mg) = 0.5 tablet.
A (0.25 tablet) incorrectly divides 0.125 by 0.5. C (1 tablet) gives full available dose, which is double the
ordered dose and could cause toxicity. D (2 tablets) is a dangerous overdose. Always verify: 0.5 tablet ×
0.25 mg = 0.125 mg ordered dose.
Q8: Which statement BEST describes the therapeutic index (TI) of a drug?
A. The ratio between the effective dose and the toxic dose
B. The margin of safety between the median effective dose (ED50) and median lethal dose
(LD50) [CORRECT]
C. The time required to reach steady-state plasma concentration
D. The degree of receptor binding affinity
Correct Answer: B Rationale: Therapeutic index = LD50/ED50, representing the margin of safety
between the dose that helps 50% of the population and the dose that kills 50% of the population. A low
TI (e.g., digoxin, lithium, warfarin, aminoglycosides) indicates a narrow safety margin requiring careful
monitoring. A is incorrect because it does not specify median doses or lethal vs. effective. C describes
time to steady-state (approximately 5 half-lives). D describes receptor affinity (Kd), unrelated to safety
margin.
Q9: [CALCULATION] A patient requires 1.5 grams of Cefazolin IV. The vial contains 2 grams in 10 mL.
How many mL should the nurse withdraw?
A. 5.5 mL
B. 6.5 mL
C. 7.5 mL [CORRECT]
D. 8.5 mL
Correct Answer: C Rationale: Concentration = 2 grams ÷ 10 mL = 0.2 g/mL (200 mg/mL). 1.5 grams ÷ 0.2
g/mL = 7.5 mL. A (5.5 mL) underestimates by 2 mL. B (6.5 mL) uses incorrect concentration calculation. D
(8.5 mL) overestimates. Formula: Desired Dose ÷ (Total Drug ÷ Total Volume) = Volume to withdraw.
Q10: A drug with a half-life of 6 hours is started. Approximately how long will it take to reach steady-
state plasma concentration?
A. 6 hours
