10th Edition Visovsky Zambroski Test Bank
Study Guide
Question 1
A patient is prescribed an enteric-coated medication. The nurse instructs the
patient not to crush or chew the tablet. What is the primary pharmacokinetic
reason for this instruction?
A) To speed up the absorption of the drug in the stomach.
B) To decrease the first-pass effect in the liver.
C) To protect the stomach lining from irritation and prevent premature drug
destruction by gastric acid.
D) To increase the protein-binding capacity of the drug.
, Answer: C) To protect the stomach lining from irritation and prevent
premature drug destruction by gastric acid.
Rationale: Enteric coatings are designed to resist dissolution in the acidic
environment of the stomach, protecting the gastric mucosa from irritation and
preserving the drug until it reaches the alkaline environment of the small
intestine. Crushing the tablet destroys this barrier, causing premature release,
potential gastric distress, or drug inactivation.
Question 2
A nurse is caring for a patient with severe chronic kidney disease (CKD) who is
prescribed a medication that is primarily excreted by the kidneys. The nurse
should anticipate which modification to the drug regimen?
A) An increase in the dosage amount.
B) A decrease in the dosing interval (giving it more frequently).
C) A decrease in the dosage amount or an increase in the dosing interval.
D) Discontinuing the drug and switching to an inhaled route.
Answer: C) A decrease in the dosage amount or an increase in the dosing
interval.
Rationale: Impaired renal function reduces the body's ability to excrete drugs,
leading to prolonged half-lives and a higher risk of toxicity. To maintain safe
therapeutic levels, the dosage must be lowered, or the time between doses must
be extended.
Question 3
, The nurse understands that a drug with a narrow therapeutic index (TI) requires
which clinical intervention?
A) Monitoring of blood glucose levels twice daily.
B) Periodic monitoring of serum drug levels to ensure safety and efficacy.
C) Immediate discontinuation if the patient experiences a mild side effect.
D) Standard dosing without any adjustments for age or weight.
Answer: B) Periodic monitoring of serum drug levels to ensure safety and
efficacy.
Rationale: A narrow therapeutic index means that the margin of safety
between a therapeutic dose and a toxic dose is very small. Close monitoring of
blood/serum concentrations (peak and trough levels) is mandatory to prevent
underdosing or toxic accumulations.
Question 4
A drug has a half-life of 6 hours. If a single dose of 400 mg is administered
intravenously at 12:00 PM, how much of the drug will remain in the patient’s
body at 12:00 AM (midnight) on the same day?
A) 200 mg
B) 100 mg
C) 50 mg
D) 25 mg
Answer: B) 100 mg.
Rationale: The time from 12:00 PM to 12:00 AM is 12 hours, which equals
exactly two half-lives ( = 2). After 6 hours (one half-life), 200 mg
remains. After another 6 hours (two half-lives), the remaining amount is split
in half again, leaving 100 mg.
, Question 5
When a drug is highly protein-bound, which physiological state puts the patient
at the highest risk for drug toxicity?
A) Hyperalbuminemia (elevated serum albumin)
B) Hypoalbuminemia (low serum albumin)
C) Increased muscle mass
D) Polycythemia (elevated red blood cells)
Answer: B) Hypoalbuminemia (low serum albumin).
Rationale: Highly protein-bound drugs look for albumin molecules to attach
to. If a patient has low albumin levels (due to malnutrition or liver disease),
there are fewer binding sites available. This results in an increased
concentration of "free," active drug in the bloodstream, heightening the risk
of an overdose/toxicity.
Question 6
Which mechanism describes a drug acting as an "agonist" at a cellular receptor
site?
A) The drug binds to the receptor and blocks endogenous chemicals from
attaching.
B) The drug alters the cell membrane without interacting with the receptor.
C) The drug binds to the receptor and mimics the natural, endogenous response
of the body.
D) The drug permanently destroys the receptor site.