NSG 5240 Advanced Pharmacology
Final Exam Practice: A Comprehensive
150-Question Bank with Detailed
Clinical Rationales
Which pharmacokinetic parameter primarily determines the
duration of a drug's effect?
Half-life. The half-life determines how long a drug remains active
in the body before levels fall below the therapeutic range. While
bioavailability and absorption affect onset, and distribution
determines spread, half-life dictates duration.
A patient with liver cirrhosis is prescribed a drug that
normally undergoes extensive first-pass metabolism. What
does the nurse practitioner anticipate?
Significantly increased bioavailability. The first-pass effect occurs
in the liver. Liver impairment means less drug is metabolized
before reaching systemic circulation, leading to higher
bioavailability and potential toxicity. This is a critical consideration
when prescribing to patients with hepatic dysfunction.
,A drug with a high volume of distribution (Vd) primarily
indicates what?
The drug extensively distributes into tissues. A high Vd suggests
the drug has left the plasma and entered tissues, often due to
lipophilicity or tissue binding. High protein binding usually
decreases Vd by keeping the drug in the vascular space.
A patient with hepatic cirrhosis is prescribed a prodrug. What
does the nurse practitioner anticipate?
Reduced conversion to active metabolite. Cirrhosis impairs liver
function, reducing the conversion of prodrugs to their active form,
potentially leading to therapeutic failure.
Which cytochrome P450 enzyme is most commonly involved
in drug-drug interactions?
CYP3A4. This enzyme metabolizes over 50% of all drugs and is
inhibited or induced by many agents, including grapefruit juice,
rifampin, and ketoconazole.
A drug's half-life is 12 hours. How many hours until steady
state is reached?
,60 hours. Steady state is achieved after approximately 4-5 half-
lives. Five times 12 hours equals 60 hours. At four half-lives,
approximately 94% of steady state is reached; at five half-lives,
approximately 97% is reached.
Which route of administration bypasses the first-pass effect?
Both sublingual and rectal. Sublingual and rectal administration
allow absorption directly into systemic circulation, partially or fully
avoiding portal circulation and first-pass metabolism in the liver.
The primary route of drug excretion for water-soluble drugs
is which of the following?
Kidney. Kidneys filter water-soluble drugs and metabolites into
urine; bile is secondary for larger molecules.
Phase II metabolism typically involves which type of reaction?
Conjugation (e.g., glucuronidation). Phase II reactions add polar
groups such as glucuronide, sulfate, or glutathione to increase
water solubility and excretion.
, Grapefruit juice increases levels of certain drugs by which
mechanism?
Inhibiting intestinal CYP3A4. Grapefruit juice inhibits intestinal
CYP3A4, reducing the first-pass metabolism of drugs in the gut
and leading to increased systemic drug levels.
The term "bioavailability" refers to what?
The amount of drug that reaches systemic circulation unchanged.
Bioavailability (F) is the fraction of an administered dose of a drug
that reaches systemic circulation unchanged. IV drugs have 100%
bioavailability; oral drugs have lower bioavailability due to first-
pass metabolism.
A drug that is a "weak acid" (e.g., aspirin, ibuprofen) will have
increased absorption in which part of the GI tract?
Stomach (low pH). Weak acids are predominantly non-ionized
(lipid-soluble) in the acidic environment of the stomach (pH 1-3),
promoting absorption. This is the principle of pH-dependent drug
absorption.
Final Exam Practice: A Comprehensive
150-Question Bank with Detailed
Clinical Rationales
Which pharmacokinetic parameter primarily determines the
duration of a drug's effect?
Half-life. The half-life determines how long a drug remains active
in the body before levels fall below the therapeutic range. While
bioavailability and absorption affect onset, and distribution
determines spread, half-life dictates duration.
A patient with liver cirrhosis is prescribed a drug that
normally undergoes extensive first-pass metabolism. What
does the nurse practitioner anticipate?
Significantly increased bioavailability. The first-pass effect occurs
in the liver. Liver impairment means less drug is metabolized
before reaching systemic circulation, leading to higher
bioavailability and potential toxicity. This is a critical consideration
when prescribing to patients with hepatic dysfunction.
,A drug with a high volume of distribution (Vd) primarily
indicates what?
The drug extensively distributes into tissues. A high Vd suggests
the drug has left the plasma and entered tissues, often due to
lipophilicity or tissue binding. High protein binding usually
decreases Vd by keeping the drug in the vascular space.
A patient with hepatic cirrhosis is prescribed a prodrug. What
does the nurse practitioner anticipate?
Reduced conversion to active metabolite. Cirrhosis impairs liver
function, reducing the conversion of prodrugs to their active form,
potentially leading to therapeutic failure.
Which cytochrome P450 enzyme is most commonly involved
in drug-drug interactions?
CYP3A4. This enzyme metabolizes over 50% of all drugs and is
inhibited or induced by many agents, including grapefruit juice,
rifampin, and ketoconazole.
A drug's half-life is 12 hours. How many hours until steady
state is reached?
,60 hours. Steady state is achieved after approximately 4-5 half-
lives. Five times 12 hours equals 60 hours. At four half-lives,
approximately 94% of steady state is reached; at five half-lives,
approximately 97% is reached.
Which route of administration bypasses the first-pass effect?
Both sublingual and rectal. Sublingual and rectal administration
allow absorption directly into systemic circulation, partially or fully
avoiding portal circulation and first-pass metabolism in the liver.
The primary route of drug excretion for water-soluble drugs
is which of the following?
Kidney. Kidneys filter water-soluble drugs and metabolites into
urine; bile is secondary for larger molecules.
Phase II metabolism typically involves which type of reaction?
Conjugation (e.g., glucuronidation). Phase II reactions add polar
groups such as glucuronide, sulfate, or glutathione to increase
water solubility and excretion.
, Grapefruit juice increases levels of certain drugs by which
mechanism?
Inhibiting intestinal CYP3A4. Grapefruit juice inhibits intestinal
CYP3A4, reducing the first-pass metabolism of drugs in the gut
and leading to increased systemic drug levels.
The term "bioavailability" refers to what?
The amount of drug that reaches systemic circulation unchanged.
Bioavailability (F) is the fraction of an administered dose of a drug
that reaches systemic circulation unchanged. IV drugs have 100%
bioavailability; oral drugs have lower bioavailability due to first-
pass metabolism.
A drug that is a "weak acid" (e.g., aspirin, ibuprofen) will have
increased absorption in which part of the GI tract?
Stomach (low pH). Weak acids are predominantly non-ionized
(lipid-soluble) in the acidic environment of the stomach (pH 1-3),
promoting absorption. This is the principle of pH-dependent drug
absorption.
