NR566 | NR566 Advanced Pharmacology for Care
of the Family Wk 5 Midterm v1 | Questions with
Correct Answers and Expert Explanation for Each
Question | Chamberlain
1. When a drug is administered orally and absorbed from the GI tract, it travels to the
liver via the portal vein where it may be extensively metabolized. This process is
known as:
A. First-pass metabolism
B. Glomerular filtration
C. Biliary excretion
D. Systemic distribution
Correct Answer: A
Expert Explanation: First-pass metabolism significantly reduces the bioavailability
of certain oral medications before they reach the systemic circulation. This effect is
why some drugs must be given in much higher oral doses than intravenous doses to
achieve the same therapeutic effect. Practitioners must consider this when
switching routes of administration for highly metabolized drugs.
2. Which of the following describes the time required for the plasma concentration of
a drug to decrease by 50%?
A. Steady state
,B. Bioavailability
C. Half-life
D. Clearance
Correct Answer: C
Expert Explanation: The half-life determines the dosing interval and the time
required to reach steady state. Generally, it takes about four to five half-lives for a
drug to be almost completely eliminated or to reach a constant plasma level.
Understanding half-life is essential for managing drug toxicity and therapeutic
window narrowness.
3. An NP is prescribing a medication that is a known substrate of the Cytochrome P450
3A4 enzyme. If the patient also takes a drug that is a potent inducer of this enzyme,
what is the likely result?
A. The substrate drug concentration will increase.
B. There will be no change in drug levels.
C. The substrate drug concentration will decrease.
D. The inducer drug will become toxic.
Correct Answer: C
,Expert Explanation: Enzyme inducers increase the metabolic activity of the
CYP450 system, leading to faster breakdown of substrate drugs. This resulting
decrease in plasma levels often necessitates a dosage increase of the substrate to
maintain therapeutic efficacy. Conversely, enzyme inhibitors would lead to
increased levels and potential toxicity of the substrate.
4. Which schedule of controlled substances has the highest potential for abuse but
also has an accepted medical use in the United States?
A. Schedule II
B. Schedule I
C. Schedule III
D. Schedule IV
Correct Answer: A
Expert Explanation: Schedule II substances, such as morphine and oxycodone,
have a high potential for abuse which may lead to severe psychological or physical
dependence. Unlike Schedule I drugs, they have a currently accepted medical use
with severe restrictions. Prescribing these requires adherence to strict federal and
state regulations, including the prohibition of refills.
, 5. A patient with chronic heart failure is prescribed Digoxin. What is the primary
mechanism of action for this medication?
A. Inhibition of the Na+/K+ ATPase pump
B. Beta-adrenergic blockade
C. Inhibition of ACE
D. Calcium channel blockade
Correct Answer: A
Expert Explanation: By inhibiting the Na+/K+ ATPase pump, Digoxin increases
intracellular sodium, which in turn leads to increased intracellular calcium through
the sodium-calcium exchanger. This results in a positive inotropic effect, increasing
the force of myocardial contraction. However, Digoxin has a narrow therapeutic
index and requires close monitoring of serum levels and electrolytes.
6. Which medication is considered the first-line therapy for a patient newly diagnosed
with Type 2 Diabetes Mellitus, assuming no contraindications?
A. Glyburide
B. Metformin
C. Liraglutide
D. Sitagliptin
of the Family Wk 5 Midterm v1 | Questions with
Correct Answers and Expert Explanation for Each
Question | Chamberlain
1. When a drug is administered orally and absorbed from the GI tract, it travels to the
liver via the portal vein where it may be extensively metabolized. This process is
known as:
A. First-pass metabolism
B. Glomerular filtration
C. Biliary excretion
D. Systemic distribution
Correct Answer: A
Expert Explanation: First-pass metabolism significantly reduces the bioavailability
of certain oral medications before they reach the systemic circulation. This effect is
why some drugs must be given in much higher oral doses than intravenous doses to
achieve the same therapeutic effect. Practitioners must consider this when
switching routes of administration for highly metabolized drugs.
2. Which of the following describes the time required for the plasma concentration of
a drug to decrease by 50%?
A. Steady state
,B. Bioavailability
C. Half-life
D. Clearance
Correct Answer: C
Expert Explanation: The half-life determines the dosing interval and the time
required to reach steady state. Generally, it takes about four to five half-lives for a
drug to be almost completely eliminated or to reach a constant plasma level.
Understanding half-life is essential for managing drug toxicity and therapeutic
window narrowness.
3. An NP is prescribing a medication that is a known substrate of the Cytochrome P450
3A4 enzyme. If the patient also takes a drug that is a potent inducer of this enzyme,
what is the likely result?
A. The substrate drug concentration will increase.
B. There will be no change in drug levels.
C. The substrate drug concentration will decrease.
D. The inducer drug will become toxic.
Correct Answer: C
,Expert Explanation: Enzyme inducers increase the metabolic activity of the
CYP450 system, leading to faster breakdown of substrate drugs. This resulting
decrease in plasma levels often necessitates a dosage increase of the substrate to
maintain therapeutic efficacy. Conversely, enzyme inhibitors would lead to
increased levels and potential toxicity of the substrate.
4. Which schedule of controlled substances has the highest potential for abuse but
also has an accepted medical use in the United States?
A. Schedule II
B. Schedule I
C. Schedule III
D. Schedule IV
Correct Answer: A
Expert Explanation: Schedule II substances, such as morphine and oxycodone,
have a high potential for abuse which may lead to severe psychological or physical
dependence. Unlike Schedule I drugs, they have a currently accepted medical use
with severe restrictions. Prescribing these requires adherence to strict federal and
state regulations, including the prohibition of refills.
, 5. A patient with chronic heart failure is prescribed Digoxin. What is the primary
mechanism of action for this medication?
A. Inhibition of the Na+/K+ ATPase pump
B. Beta-adrenergic blockade
C. Inhibition of ACE
D. Calcium channel blockade
Correct Answer: A
Expert Explanation: By inhibiting the Na+/K+ ATPase pump, Digoxin increases
intracellular sodium, which in turn leads to increased intracellular calcium through
the sodium-calcium exchanger. This results in a positive inotropic effect, increasing
the force of myocardial contraction. However, Digoxin has a narrow therapeutic
index and requires close monitoring of serum levels and electrolytes.
6. Which medication is considered the first-line therapy for a patient newly diagnosed
with Type 2 Diabetes Mellitus, assuming no contraindications?
A. Glyburide
B. Metformin
C. Liraglutide
D. Sitagliptin
