NUR 2407 Pharmacology Test 1
Latest 2026/2027 - Questions and Verified Answers
Rasmussen University - Pharmacology
Total Questions 120
Cognitive Levels 30% Recall / 50% Application / 20% Analysis
Question Style 80% Scenario-based / 20% Direct Recall
Sections 8
Format Multiple Choice (4 options, single best answer)
Content Domains Pharmacokinetics, Pharmacodynamics, Calculations, Lifespan, ANS, Cardio, Respiratory/GI, Safe Practice
Curriculum 2026/2027 Rasmussen NUR 2407
Exam Instructions: This comprehensive 120-question exam assesses pharmacology knowledge across eight content
domains: pharmacokinetics, pharmacodynamics, medication administration, lifespan considerations, autonomic
pharmacology, cardiovascular pharmacology, respiratory/GI pharmacology, and patient education/safe practice. Select the
single best answer for each question. Rationales include mechanism of action, monitoring parameters, adverse effects, and
patient safety considerations. Content reflects current (2026/2027) pharmacology standards and medication safety
guidelines.
Section 1: Pharmacologic Principles and Pharmacokinetics
Absorption, Distribution, Metabolism, Excretion, Half-Life, and Steady State (Q1-Q16)
Q1: A nurse is teaching a patient about a medication's 'first-pass effect.' Which statement by the nurse is most
accurate?
A. 'The first-pass effect means the drug is absorbed into the bloodstream directly.'
B. 'The first-pass effect occurs when a drug taken orally is metabolized by the liver before reaching systemic
circulation, reducing the amount of active drug available.' [CORRECT]
C. 'The first-pass effect occurs in the kidneys.'
D. 'The first-pass effect only occurs with IV medications.'
Correct Answer: B
Rationale: The first-pass effect (presystemic metabolism) occurs when an oral drug is absorbed through the GI tract and
transported via the portal vein to the liver, where a portion is metabolized before reaching systemic circulation. This reduces
bioavailability of oral drugs. Sublingual, buccal, transdermal, IV, IM, and rectal routes (partially) bypass the first-pass
effect. The IV route provides 100% bioavailability. The first-pass effect explains why oral doses of some drugs (e.g.,
morphine, propranolol, nitroglycerin) are higher than parenteral doses. Alternative routes (sublingual nitroglycerin) avoid
first-pass metabolism for rapid effect. Knowledge of first-pass effect guides route selection and dosing.
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 1
, Q2: A patient is prescribed oral morphine 30 mg; the IV dose would be approximately 10 mg. This difference in
dosing is best explained by:
A. Increased absorption of oral morphine
B. First-pass hepatic metabolism of oral morphine reduces bioavailability, requiring higher oral dose to
achieve equivalent therapeutic effect [CORRECT]
C. IV morphine has higher protein binding
D. Oral morphine has a longer half-life
Correct Answer: B
Rationale: Oral morphine undergoes significant first-pass metabolism in the liver (about 50-70% metabolized before
reaching systemic circulation), reducing bioavailability to approximately 30-40%. To achieve equivalent therapeutic effect,
the oral dose must be 2-3 times higher than IV. IV morphine bypasses first-pass metabolism (100% bioavailability). This
principle applies to many drugs with significant first-pass effect (propranolol, nitroglycerin, verapamil, lidocaine,
levodopa). Recognizing first-pass effect guides route selection and dose adjustment. Other factors affecting bioavailability:
drug formulation, GI pH, food, malabsorption, GI motility, hepatic dysfunction, drug interactions.
Q3: A drug with high protein binding (e.g., 95% bound to albumin) is administered to a patient with
hypoalbuminemia. The nurse should anticipate:
A. Decreased drug effect - less drug is available in free form
B. Increased drug effect and potential toxicity - more free (active) drug is available due to less protein binding
[CORRECT]
C. No change in drug effect
D. Decreased drug half-life
Correct Answer: B
Rationale: Only 'free' (unbound) drug is pharmacologically active and able to bind receptors, distribute to tissues, and be
metabolized/excreted. Albumin is the primary plasma protein binding acidic drugs (alpha-1-acid glycoprotein binds basic
drugs). In hypoalbuminemia (liver disease, nephrotic syndrome, malnutrition, burns, inflammation), less drug is bound,
more is free, leading to increased effect and toxicity risk. Examples: phenytoin, warfarin, valproic acid, digoxin. Dosing
adjustments required; monitor therapeutic levels closely. Other drugs that displace protein-bound drugs (sulfonamides,
salicylates, NSAIDs) can also increase free fraction. Total drug levels may be misleading in hypoalbuminemia; free drug
levels are more accurate.
Q4: A drug is administered IV. Which pharmacokinetic parameter is directly AFFECTED compared to oral
administration?
A. Absorption - IV route has 100% bioavailability (no absorption process) [CORRECT]
B. Metabolism
C. Excretion
D. Distribution
Correct Answer: A
Rationale: IV administration bypasses absorption (drug placed directly into circulation), achieving 100% bioavailability.
The other pharmacokinetic phases (distribution, metabolism, excretion) are not directly affected by route. Distribution
depends on blood flow, protein binding, lipid solubility. Metabolism occurs primarily in the liver (CYP450 enzymes).
Excretion is primarily through kidneys (some biliary). Routes affecting absorption: oral (first-pass), IM (blood flow, muscle
activity), subcutaneous (blood flow, volume), sublingual (rapid, no first-pass), transdermal (slow, steady), rectal (partial
first-pass). IV provides rapid onset (1-5 minutes), accurate dosing, used for emergencies, high-alert medications, and drugs
with poor oral bioavailability. Risks: infection, infiltration, phlebitis, embolism, anaphylaxis.
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 2
, Q5: A patient is receiving IV phenytoin. The nurse recalls that IV phenytoin must be administered slowly (max 50
mg/min in adults). The rationale is to prevent:
A. Hypotension and cardiac arrhythmias (pharmacologic effects when administered rapidly) [CORRECT]
B. First-pass effect
C. Increased absorption
D. Hepatic enzyme induction
Correct Answer: A
Rationale: IV phenytoin must be administered slowly (≤ 50 mg/min in adults, ≤ 25 mg/min in elderly or cardiac patients) to
prevent hypotension, bradycardia, AV block, ventricular fibrillation, and cardiac arrest due to the propylene glycol solvent.
Other considerations: phenytoin is highly alkaline (pH 12) - irritating to veins (use large vein, flush with NS); incompatible
with dextrose-containing solutions (precipitates) - flush line before/after with NS; central line preferred for prolonged
therapy; cardiac monitoring during IV administration; emergency resuscitation equipment available. Phenytoin follows
zero-order (nonlinear) kinetics - small dose increases cause large serum level increases. Therapeutic level: 10-20 mcg/mL.
Toxicity: nystagmus, ataxia, confusion, seizures. The slow rate prevents acute cardiovascular collapse.
Q6: A drug has a half-life (t1/2) of 12 hours. Approximately how long will it take to reach steady state?
A. 12 hours
B. About 60 hours (4-5 half-lives: 4-5 x 12 = 48-60 hours) to reach approximately 94-97% steady state
[CORRECT]
C. 24 hours
D. 6 hours
Correct Answer: B
Rationale: Steady state is the equilibrium between drug administration and elimination. Time to reach steady state is
approximately 4-5 half-lives (about 94-97% of steady state). For t1/2 = 12 hours: 5 half-lives = 60 hours (about 2.5 days).
At 1 half-life = 50%, 2 = 75%, 3 = 87.5%, 4 = 93.75%, 5 = 96.9%. Practical implications: (1) For drugs with long half-lives
(e.g., digoxin, fluoxetine - 7+ days), steady state takes weeks - loading dose may be used; (2) For short half-life drugs (e.g.,
insulin, narcotics), steady state reached quickly; (3) Therapeutic drug levels are interpreted after steady state achieved (or 5
half-lives after dose change); (4) Drug elimination time also follows half-life (5 half-lives for complete elimination after last
dose). Loading dose: large initial dose to rapidly achieve therapeutic level.
Q7: A patient is prescribed digoxin with a half-life of 36 hours. After 7 days without a dose, what percentage of the
drug remains in the body?
A. About 6% (after 7 days = 168 hours, which is about 4-5 half-lives; ~6-13% remains) [CORRECT]
B. About 50%
C. About 25%
D. About 0%
Correct Answer: A
Rationale: Calculations: 7 days = 168 hours. Half-life = 36 hours. Number of half-lives = = 4.67. Drug remaining
after n half-lives = (1/2)^n = (1/2)^4.67 = 0.039 (about 4% of peak). For practical purposes, after 5 half-lives, about 3%
remains (considered essentially eliminated). Digoxin has a long half-life (36-48 hours) due to tissue distribution. Loading
dose may be used to achieve therapeutic level quickly (10 mcg/kg total). Steady state reached in 7-10 days. Therapeutic
level: 0.5-2 ng/mL (narrow therapeutic index). Toxicity: nausea, vomiting, visual disturbances (yellow-green halos,
xanthopsia), arrhythmias (PVCs, atrial tachyarrhythmias, bradycardia). Hypokalemia, hypomagnesemia, hypercalcemia,
renal dysfunction, hypothyroidism increase toxicity.
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 3
, Q8: A loading dose of a medication is typically administered when:
A. The drug has a short half-life
B. The drug has a long half-life and rapid therapeutic effect is needed (e.g., digoxin, antiarrhythmics,
antiepileptics, antibiotics in critically ill) [CORRECT]
C. The patient is pregnant
D. The patient is elderly
Correct Answer: B
Rationale: Loading dose: a single, large dose administered initially to rapidly achieve therapeutic plasma concentration,
used when: (1) drug has long half-life (steady state takes too long); (2) urgent need for therapeutic effect (acute MI, sepsis,
status epilepticus, AFib). Common loading-dose drugs: digoxin (10 mcg/kg), amiodarone (load 800-1600 mg/day x 1-3
weeks), phenytoin (10-15 mg/kg), voriconazole, vancomycin (15-20 mg/kg). After loading dose, maintenance doses
continue at standard interval. Loading dose calculation: LD = (Vd x Cp_target) / F (where Vd = volume of distribution, Cp
= target concentration, F = bioavailability). Risks: toxicity if dose too high; careful monitoring. Without loading dose, drugs
with long half-lives (e.g., digoxin 36 hr t1/2 - 7-10 days to steady state) cause delay in therapeutic effect.
Q9: The volume of distribution (Vd) of a drug is best described as:
A. The amount of drug administered
B. A theoretical volume that represents the apparent space in the body available to contain the drug, calculated
as dose / plasma concentration [CORRECT]
C. Blood volume only
D. Total body water
Correct Answer: B
Rationale: Volume of distribution (Vd): theoretical volume that would be required to contain the total absorbed drug at the
same concentration as in plasma. Calculated: Vd = dose / plasma concentration. Low Vd (< 10 L): drug remains in vascular
space (large molecules, high protein binding) - heparin, insulin, warfarin. Moderate Vd (10-30 L): distributes to
extracellular fluid (water-soluble drugs) - gentamicin, digoxin (some). High Vd (> 100 L): distributes extensively to tissues
(lipid-soluble drugs) - amiodarone, digoxin (mainly), TCAs, propranolol. High Vd: often reflects tissue binding, requires
loading dose, longer half-life (extensive tissue distribution). Vd affects: drug concentration, dose calculation, dialysis
effectiveness (drugs with low Vd are more easily dialyzed). Disease states affecting Vd: edema, ascites, dehydration,
obesity.
Q10: Which of the following statements about drug metabolism (Phase I and Phase II reactions) is correct?
A. Phase I reactions always produce active metabolites
B. Phase I reactions typically involve CYP450 enzymes that add or expose functional groups (oxidation,
reduction, hydrolysis); Phase II reactions conjugate (attach) molecules to make drugs more water-soluble for
excretion [CORRECT]
C. Phase II occurs before Phase I
D. Only Phase I requires enzymes
Correct Answer: B
Rationale: Drug metabolism (biotransformation): liver is primary site (also GI, lungs, kidney, skin). Phase I reactions:
CYP450 enzymes (mostly CYP3A4, CYP2D6, CYP2C9, CYP1A2) catalyze oxidation, reduction, hydrolysis - add or
expose functional groups. Products may be active (e.g., codeine -> morphine via CYP2D6), inactive, or reactive (toxic).
Phase II reactions: conjugation (attach glucuronic acid, sulfate, glutathione, amino acids) - make drugs more water-soluble
for renal/biliary excretion. Products typically inactive (exception: morphine-6-glucuronide more active than morphine).
Phase II enzymes: UGT (glucuronidation), SULT (sulfation), GST (glutathione), NAT (acetylation). Some drugs undergo
only Phase I or II. Genetic polymorphisms affect metabolism (CYP2D6 poor vs. ultra-rapid metabolizers; TPMT,
UGT1A1).
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 4
Latest 2026/2027 - Questions and Verified Answers
Rasmussen University - Pharmacology
Total Questions 120
Cognitive Levels 30% Recall / 50% Application / 20% Analysis
Question Style 80% Scenario-based / 20% Direct Recall
Sections 8
Format Multiple Choice (4 options, single best answer)
Content Domains Pharmacokinetics, Pharmacodynamics, Calculations, Lifespan, ANS, Cardio, Respiratory/GI, Safe Practice
Curriculum 2026/2027 Rasmussen NUR 2407
Exam Instructions: This comprehensive 120-question exam assesses pharmacology knowledge across eight content
domains: pharmacokinetics, pharmacodynamics, medication administration, lifespan considerations, autonomic
pharmacology, cardiovascular pharmacology, respiratory/GI pharmacology, and patient education/safe practice. Select the
single best answer for each question. Rationales include mechanism of action, monitoring parameters, adverse effects, and
patient safety considerations. Content reflects current (2026/2027) pharmacology standards and medication safety
guidelines.
Section 1: Pharmacologic Principles and Pharmacokinetics
Absorption, Distribution, Metabolism, Excretion, Half-Life, and Steady State (Q1-Q16)
Q1: A nurse is teaching a patient about a medication's 'first-pass effect.' Which statement by the nurse is most
accurate?
A. 'The first-pass effect means the drug is absorbed into the bloodstream directly.'
B. 'The first-pass effect occurs when a drug taken orally is metabolized by the liver before reaching systemic
circulation, reducing the amount of active drug available.' [CORRECT]
C. 'The first-pass effect occurs in the kidneys.'
D. 'The first-pass effect only occurs with IV medications.'
Correct Answer: B
Rationale: The first-pass effect (presystemic metabolism) occurs when an oral drug is absorbed through the GI tract and
transported via the portal vein to the liver, where a portion is metabolized before reaching systemic circulation. This reduces
bioavailability of oral drugs. Sublingual, buccal, transdermal, IV, IM, and rectal routes (partially) bypass the first-pass
effect. The IV route provides 100% bioavailability. The first-pass effect explains why oral doses of some drugs (e.g.,
morphine, propranolol, nitroglycerin) are higher than parenteral doses. Alternative routes (sublingual nitroglycerin) avoid
first-pass metabolism for rapid effect. Knowledge of first-pass effect guides route selection and dosing.
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 1
, Q2: A patient is prescribed oral morphine 30 mg; the IV dose would be approximately 10 mg. This difference in
dosing is best explained by:
A. Increased absorption of oral morphine
B. First-pass hepatic metabolism of oral morphine reduces bioavailability, requiring higher oral dose to
achieve equivalent therapeutic effect [CORRECT]
C. IV morphine has higher protein binding
D. Oral morphine has a longer half-life
Correct Answer: B
Rationale: Oral morphine undergoes significant first-pass metabolism in the liver (about 50-70% metabolized before
reaching systemic circulation), reducing bioavailability to approximately 30-40%. To achieve equivalent therapeutic effect,
the oral dose must be 2-3 times higher than IV. IV morphine bypasses first-pass metabolism (100% bioavailability). This
principle applies to many drugs with significant first-pass effect (propranolol, nitroglycerin, verapamil, lidocaine,
levodopa). Recognizing first-pass effect guides route selection and dose adjustment. Other factors affecting bioavailability:
drug formulation, GI pH, food, malabsorption, GI motility, hepatic dysfunction, drug interactions.
Q3: A drug with high protein binding (e.g., 95% bound to albumin) is administered to a patient with
hypoalbuminemia. The nurse should anticipate:
A. Decreased drug effect - less drug is available in free form
B. Increased drug effect and potential toxicity - more free (active) drug is available due to less protein binding
[CORRECT]
C. No change in drug effect
D. Decreased drug half-life
Correct Answer: B
Rationale: Only 'free' (unbound) drug is pharmacologically active and able to bind receptors, distribute to tissues, and be
metabolized/excreted. Albumin is the primary plasma protein binding acidic drugs (alpha-1-acid glycoprotein binds basic
drugs). In hypoalbuminemia (liver disease, nephrotic syndrome, malnutrition, burns, inflammation), less drug is bound,
more is free, leading to increased effect and toxicity risk. Examples: phenytoin, warfarin, valproic acid, digoxin. Dosing
adjustments required; monitor therapeutic levels closely. Other drugs that displace protein-bound drugs (sulfonamides,
salicylates, NSAIDs) can also increase free fraction. Total drug levels may be misleading in hypoalbuminemia; free drug
levels are more accurate.
Q4: A drug is administered IV. Which pharmacokinetic parameter is directly AFFECTED compared to oral
administration?
A. Absorption - IV route has 100% bioavailability (no absorption process) [CORRECT]
B. Metabolism
C. Excretion
D. Distribution
Correct Answer: A
Rationale: IV administration bypasses absorption (drug placed directly into circulation), achieving 100% bioavailability.
The other pharmacokinetic phases (distribution, metabolism, excretion) are not directly affected by route. Distribution
depends on blood flow, protein binding, lipid solubility. Metabolism occurs primarily in the liver (CYP450 enzymes).
Excretion is primarily through kidneys (some biliary). Routes affecting absorption: oral (first-pass), IM (blood flow, muscle
activity), subcutaneous (blood flow, volume), sublingual (rapid, no first-pass), transdermal (slow, steady), rectal (partial
first-pass). IV provides rapid onset (1-5 minutes), accurate dosing, used for emergencies, high-alert medications, and drugs
with poor oral bioavailability. Risks: infection, infiltration, phlebitis, embolism, anaphylaxis.
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 2
, Q5: A patient is receiving IV phenytoin. The nurse recalls that IV phenytoin must be administered slowly (max 50
mg/min in adults). The rationale is to prevent:
A. Hypotension and cardiac arrhythmias (pharmacologic effects when administered rapidly) [CORRECT]
B. First-pass effect
C. Increased absorption
D. Hepatic enzyme induction
Correct Answer: A
Rationale: IV phenytoin must be administered slowly (≤ 50 mg/min in adults, ≤ 25 mg/min in elderly or cardiac patients) to
prevent hypotension, bradycardia, AV block, ventricular fibrillation, and cardiac arrest due to the propylene glycol solvent.
Other considerations: phenytoin is highly alkaline (pH 12) - irritating to veins (use large vein, flush with NS); incompatible
with dextrose-containing solutions (precipitates) - flush line before/after with NS; central line preferred for prolonged
therapy; cardiac monitoring during IV administration; emergency resuscitation equipment available. Phenytoin follows
zero-order (nonlinear) kinetics - small dose increases cause large serum level increases. Therapeutic level: 10-20 mcg/mL.
Toxicity: nystagmus, ataxia, confusion, seizures. The slow rate prevents acute cardiovascular collapse.
Q6: A drug has a half-life (t1/2) of 12 hours. Approximately how long will it take to reach steady state?
A. 12 hours
B. About 60 hours (4-5 half-lives: 4-5 x 12 = 48-60 hours) to reach approximately 94-97% steady state
[CORRECT]
C. 24 hours
D. 6 hours
Correct Answer: B
Rationale: Steady state is the equilibrium between drug administration and elimination. Time to reach steady state is
approximately 4-5 half-lives (about 94-97% of steady state). For t1/2 = 12 hours: 5 half-lives = 60 hours (about 2.5 days).
At 1 half-life = 50%, 2 = 75%, 3 = 87.5%, 4 = 93.75%, 5 = 96.9%. Practical implications: (1) For drugs with long half-lives
(e.g., digoxin, fluoxetine - 7+ days), steady state takes weeks - loading dose may be used; (2) For short half-life drugs (e.g.,
insulin, narcotics), steady state reached quickly; (3) Therapeutic drug levels are interpreted after steady state achieved (or 5
half-lives after dose change); (4) Drug elimination time also follows half-life (5 half-lives for complete elimination after last
dose). Loading dose: large initial dose to rapidly achieve therapeutic level.
Q7: A patient is prescribed digoxin with a half-life of 36 hours. After 7 days without a dose, what percentage of the
drug remains in the body?
A. About 6% (after 7 days = 168 hours, which is about 4-5 half-lives; ~6-13% remains) [CORRECT]
B. About 50%
C. About 25%
D. About 0%
Correct Answer: A
Rationale: Calculations: 7 days = 168 hours. Half-life = 36 hours. Number of half-lives = = 4.67. Drug remaining
after n half-lives = (1/2)^n = (1/2)^4.67 = 0.039 (about 4% of peak). For practical purposes, after 5 half-lives, about 3%
remains (considered essentially eliminated). Digoxin has a long half-life (36-48 hours) due to tissue distribution. Loading
dose may be used to achieve therapeutic level quickly (10 mcg/kg total). Steady state reached in 7-10 days. Therapeutic
level: 0.5-2 ng/mL (narrow therapeutic index). Toxicity: nausea, vomiting, visual disturbances (yellow-green halos,
xanthopsia), arrhythmias (PVCs, atrial tachyarrhythmias, bradycardia). Hypokalemia, hypomagnesemia, hypercalcemia,
renal dysfunction, hypothyroidism increase toxicity.
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 3
, Q8: A loading dose of a medication is typically administered when:
A. The drug has a short half-life
B. The drug has a long half-life and rapid therapeutic effect is needed (e.g., digoxin, antiarrhythmics,
antiepileptics, antibiotics in critically ill) [CORRECT]
C. The patient is pregnant
D. The patient is elderly
Correct Answer: B
Rationale: Loading dose: a single, large dose administered initially to rapidly achieve therapeutic plasma concentration,
used when: (1) drug has long half-life (steady state takes too long); (2) urgent need for therapeutic effect (acute MI, sepsis,
status epilepticus, AFib). Common loading-dose drugs: digoxin (10 mcg/kg), amiodarone (load 800-1600 mg/day x 1-3
weeks), phenytoin (10-15 mg/kg), voriconazole, vancomycin (15-20 mg/kg). After loading dose, maintenance doses
continue at standard interval. Loading dose calculation: LD = (Vd x Cp_target) / F (where Vd = volume of distribution, Cp
= target concentration, F = bioavailability). Risks: toxicity if dose too high; careful monitoring. Without loading dose, drugs
with long half-lives (e.g., digoxin 36 hr t1/2 - 7-10 days to steady state) cause delay in therapeutic effect.
Q9: The volume of distribution (Vd) of a drug is best described as:
A. The amount of drug administered
B. A theoretical volume that represents the apparent space in the body available to contain the drug, calculated
as dose / plasma concentration [CORRECT]
C. Blood volume only
D. Total body water
Correct Answer: B
Rationale: Volume of distribution (Vd): theoretical volume that would be required to contain the total absorbed drug at the
same concentration as in plasma. Calculated: Vd = dose / plasma concentration. Low Vd (< 10 L): drug remains in vascular
space (large molecules, high protein binding) - heparin, insulin, warfarin. Moderate Vd (10-30 L): distributes to
extracellular fluid (water-soluble drugs) - gentamicin, digoxin (some). High Vd (> 100 L): distributes extensively to tissues
(lipid-soluble drugs) - amiodarone, digoxin (mainly), TCAs, propranolol. High Vd: often reflects tissue binding, requires
loading dose, longer half-life (extensive tissue distribution). Vd affects: drug concentration, dose calculation, dialysis
effectiveness (drugs with low Vd are more easily dialyzed). Disease states affecting Vd: edema, ascites, dehydration,
obesity.
Q10: Which of the following statements about drug metabolism (Phase I and Phase II reactions) is correct?
A. Phase I reactions always produce active metabolites
B. Phase I reactions typically involve CYP450 enzymes that add or expose functional groups (oxidation,
reduction, hydrolysis); Phase II reactions conjugate (attach) molecules to make drugs more water-soluble for
excretion [CORRECT]
C. Phase II occurs before Phase I
D. Only Phase I requires enzymes
Correct Answer: B
Rationale: Drug metabolism (biotransformation): liver is primary site (also GI, lungs, kidney, skin). Phase I reactions:
CYP450 enzymes (mostly CYP3A4, CYP2D6, CYP2C9, CYP1A2) catalyze oxidation, reduction, hydrolysis - add or
expose functional groups. Products may be active (e.g., codeine -> morphine via CYP2D6), inactive, or reactive (toxic).
Phase II reactions: conjugation (attach glucuronic acid, sulfate, glutathione, amino acids) - make drugs more water-soluble
for renal/biliary excretion. Products typically inactive (exception: morphine-6-glucuronide more active than morphine).
Phase II enzymes: UGT (glucuronidation), SULT (sulfation), GST (glutathione), NAT (acetylation). Some drugs undergo
only Phase I or II. Genetic polymorphisms affect metabolism (CYP2D6 poor vs. ultra-rapid metabolizers; TPMT,
UGT1A1).
NUR 2407 Pharmacology Test 1 - Rasmussen University Page 4
