NR 293 Pharmacology – Exam 3 Questions and Answers|
Updated| Pass Guaranteed| Chamberlain University
Question 1
Which of the following best describes the primary focus of pharmacokinetics?
A) The study of how drugs produce their therapeutic effects at receptor sites
B) The study of how the body absorbs, distributes, metabolizes, and excretes drugs
C) The study of the clinical use of drugs to prevent and treat disease
D) The study of how genetic factors influence individual drug responses
Answer
Answer: B
Rationale
Pharmacokinetics encompasses the four major processes of absorption, distribution, metabolism, and
excretion—often remembered as ADME. This field explains how drug concentration changes over time
within the body. Pharmacodynamics, by contrast, focuses on what the drug does to the body, including
receptor interactions and therapeutic effects .
Question 2
What is the primary function of the first-pass effect in oral drug administration?
A) It enhances drug absorption by increasing gastric motility
B) It reduces drug bioavailability through hepatic metabolism before systemic circulation
C) It allows drugs to bypass the liver and enter circulation directly
D) It increases the rate at which drugs are excreted by the kidneys
Answer
Answer: B
Rationale
The first-pass effect occurs when orally administered drugs are absorbed from the gastrointestinal
tract and transported via the portal vein to the liver, where a portion is metabolized before reaching
systemic circulation. This reduces the amount of active drug available to produce therapeutic effects.
Intravenous administration bypasses this effect entirely, providing 100% bioavailability .
,Question 3
A drug has a half-life of 6 hours. Approximately how long will it take for the drug to reach
steady-state concentration with repeated dosing?
A) 6 hours
B) 12 hours
C) 24 hours
D) 36 hours
Answer
Answer: C
Rationale
Steady-state concentration is typically achieved after approximately 4 to 5 half-lives of a drug
administered at regular intervals. With a half-life of 6 hours, four half-lives equal 24 hours and five half-
lives equal 30 hours. Therefore, steady state is reached at approximately 24 hours .
Question 4
A 68-year-old male receives an intravenous dose of gentamicin. The nurse understands that
distribution of this hydrophilic drug is largely confined to the extracellular fluid. Which
pharmacokinetic property explains why aminoglycosides have a relatively small volume of
distribution?
A) High water solubility with low tissue protein binding
B) High lipid solubility with extensive adipose accumulation
C) Active transport across the blood-brain barrier
D) Rapid hepatic metabolism before reaching tissues
Answer
Answer: A
Rationale
Aminoglycosides such as gentamicin are highly water-soluble and poorly bind plasma proteins,
restricting distribution primarily to extracellular fluid and giving a small volume of distribution. High lipid
solubility would produce a large volume of distribution by allowing tissue accumulation .
2
,Question 5
Most oral medications are absorbed primarily in which segment of the gastrointestinal tract?
A) The stomach, where acidity activates most drugs
B) The small intestine, especially the duodenum and jejunum
C) The colon, where bacterial flora metabolize drugs
D) The esophagus, where contact time is longest
Answer
Answer: B
Rationale
The small intestine, particularly the duodenum and jejunum, has the largest absorptive surface area
and is the primary site of drug absorption due to villi and microvilli. The stomach absorbs very few
drugs because of its thick mucus layer and limited surface area .
Question 6
A 42-year-old male receives IV morphine for postoperative pain. The nurse recognizes that
morphine undergoes significant first-pass metabolism when given orally. The first-pass effect
primarily reduces bioavailability through metabolism in which organ?
A) The lungs via pulmonary endothelial enzymes before cardiac output
B) The kidneys via glomerular filtration before tubular secretion
C) The liver via the portal circulation before systemic distribution
D) The stomach via gastric acid hydrolysis before intestinal absorption
Answer
Answer: C
Rationale
The first-pass effect describes hepatic metabolism of orally administered drugs before they reach
systemic circulation, significantly reducing bioavailability for drugs like morphine and propranolol.
Renal filtration occurs after systemic distribution, so the alternative mislocates the metabolic site .
Question 7
A 72-year-old female with hepatic cirrhosis is started on a normally low-extraction
3
, benzodiazepine, and the nurse anticipates dose reduction. Phase I hepatic metabolism, which
declines with aging and liver disease, primarily involves which biochemical reaction?
A) Biliary excretion of unchanged parent drug
B) Conjugation with glucuronic acid or sulfate to increase water solubility
C) Active tubular secretion into the renal proximal tubule
D) Oxidation, reduction, and hydrolysis reactions often catalyzed by cytochrome P450
Answer
Answer: D
Rationale
Phase I hepatic metabolism primarily involves oxidation, reduction, and hydrolysis reactions, many
catalyzed by the cytochrome P450 enzyme system. These reactions introduce or expose functional
groups, preparing drugs for phase II conjugation or excretion .
Question 8
A patient's lithium level is 1.2 mEq/L. Based on this value, what is the nurse's priority action
regarding the scheduled daily dose?
A) Hold the dose and notify the provider due to toxicity
B) Administer the dose as scheduled, as this level is within the therapeutic range
C) Administer half the dose to prevent toxicity
D) Hold the dose and check the level again
Answer
Answer: B
Rationale
The therapeutic range for lithium is approximately 0.6–1.2 mEq/L. A level of 1.2 mEq/L is at the upper
end of the therapeutic range, and the dose should be administered as scheduled while monitoring for
signs of toxicity .
Question 9
Which of the following describes a predictable, dose-related adverse reaction?
A) Anaphylaxis
B) Side effect
4
Updated| Pass Guaranteed| Chamberlain University
Question 1
Which of the following best describes the primary focus of pharmacokinetics?
A) The study of how drugs produce their therapeutic effects at receptor sites
B) The study of how the body absorbs, distributes, metabolizes, and excretes drugs
C) The study of the clinical use of drugs to prevent and treat disease
D) The study of how genetic factors influence individual drug responses
Answer
Answer: B
Rationale
Pharmacokinetics encompasses the four major processes of absorption, distribution, metabolism, and
excretion—often remembered as ADME. This field explains how drug concentration changes over time
within the body. Pharmacodynamics, by contrast, focuses on what the drug does to the body, including
receptor interactions and therapeutic effects .
Question 2
What is the primary function of the first-pass effect in oral drug administration?
A) It enhances drug absorption by increasing gastric motility
B) It reduces drug bioavailability through hepatic metabolism before systemic circulation
C) It allows drugs to bypass the liver and enter circulation directly
D) It increases the rate at which drugs are excreted by the kidneys
Answer
Answer: B
Rationale
The first-pass effect occurs when orally administered drugs are absorbed from the gastrointestinal
tract and transported via the portal vein to the liver, where a portion is metabolized before reaching
systemic circulation. This reduces the amount of active drug available to produce therapeutic effects.
Intravenous administration bypasses this effect entirely, providing 100% bioavailability .
,Question 3
A drug has a half-life of 6 hours. Approximately how long will it take for the drug to reach
steady-state concentration with repeated dosing?
A) 6 hours
B) 12 hours
C) 24 hours
D) 36 hours
Answer
Answer: C
Rationale
Steady-state concentration is typically achieved after approximately 4 to 5 half-lives of a drug
administered at regular intervals. With a half-life of 6 hours, four half-lives equal 24 hours and five half-
lives equal 30 hours. Therefore, steady state is reached at approximately 24 hours .
Question 4
A 68-year-old male receives an intravenous dose of gentamicin. The nurse understands that
distribution of this hydrophilic drug is largely confined to the extracellular fluid. Which
pharmacokinetic property explains why aminoglycosides have a relatively small volume of
distribution?
A) High water solubility with low tissue protein binding
B) High lipid solubility with extensive adipose accumulation
C) Active transport across the blood-brain barrier
D) Rapid hepatic metabolism before reaching tissues
Answer
Answer: A
Rationale
Aminoglycosides such as gentamicin are highly water-soluble and poorly bind plasma proteins,
restricting distribution primarily to extracellular fluid and giving a small volume of distribution. High lipid
solubility would produce a large volume of distribution by allowing tissue accumulation .
2
,Question 5
Most oral medications are absorbed primarily in which segment of the gastrointestinal tract?
A) The stomach, where acidity activates most drugs
B) The small intestine, especially the duodenum and jejunum
C) The colon, where bacterial flora metabolize drugs
D) The esophagus, where contact time is longest
Answer
Answer: B
Rationale
The small intestine, particularly the duodenum and jejunum, has the largest absorptive surface area
and is the primary site of drug absorption due to villi and microvilli. The stomach absorbs very few
drugs because of its thick mucus layer and limited surface area .
Question 6
A 42-year-old male receives IV morphine for postoperative pain. The nurse recognizes that
morphine undergoes significant first-pass metabolism when given orally. The first-pass effect
primarily reduces bioavailability through metabolism in which organ?
A) The lungs via pulmonary endothelial enzymes before cardiac output
B) The kidneys via glomerular filtration before tubular secretion
C) The liver via the portal circulation before systemic distribution
D) The stomach via gastric acid hydrolysis before intestinal absorption
Answer
Answer: C
Rationale
The first-pass effect describes hepatic metabolism of orally administered drugs before they reach
systemic circulation, significantly reducing bioavailability for drugs like morphine and propranolol.
Renal filtration occurs after systemic distribution, so the alternative mislocates the metabolic site .
Question 7
A 72-year-old female with hepatic cirrhosis is started on a normally low-extraction
3
, benzodiazepine, and the nurse anticipates dose reduction. Phase I hepatic metabolism, which
declines with aging and liver disease, primarily involves which biochemical reaction?
A) Biliary excretion of unchanged parent drug
B) Conjugation with glucuronic acid or sulfate to increase water solubility
C) Active tubular secretion into the renal proximal tubule
D) Oxidation, reduction, and hydrolysis reactions often catalyzed by cytochrome P450
Answer
Answer: D
Rationale
Phase I hepatic metabolism primarily involves oxidation, reduction, and hydrolysis reactions, many
catalyzed by the cytochrome P450 enzyme system. These reactions introduce or expose functional
groups, preparing drugs for phase II conjugation or excretion .
Question 8
A patient's lithium level is 1.2 mEq/L. Based on this value, what is the nurse's priority action
regarding the scheduled daily dose?
A) Hold the dose and notify the provider due to toxicity
B) Administer the dose as scheduled, as this level is within the therapeutic range
C) Administer half the dose to prevent toxicity
D) Hold the dose and check the level again
Answer
Answer: B
Rationale
The therapeutic range for lithium is approximately 0.6–1.2 mEq/L. A level of 1.2 mEq/L is at the upper
end of the therapeutic range, and the dose should be administered as scheduled while monitoring for
signs of toxicity .
Question 9
Which of the following describes a predictable, dose-related adverse reaction?
A) Anaphylaxis
B) Side effect
4
