Therapeutic drug monitoring

Question 1

1. Pharmacokinetics refers to the branch of pharmacology
   that deals with:

a. the time-dependent processes of absorption, distribution, metabolism, and the excretion of drugs and their
metabolites from the body.
b. the relationship between a drug’s concentration and its
effects on its target receptor.
c. the toxic effects of a drug.
d. the distribution of drugs to patients.
e. the study of time-dependent effects of a drug on the body.

Answer 1

a. the time-dependent processes of absorption, distribution, metabolism, and the excretion of drugs and their
metabolites from the body.

Question 2

2. Which of the following statements are true regarding phenytoin?

a. Phenytoin exhibits zero-order kinetics with saturation
of metabolism at conventional doses.
b. Phenytoin binds tightly to red blood cells and requires
whole blood testing.
c. Phenytoin steady-state concentration is linearly proportion to the dose in most patients.
d. Phenytoin is excreted mostly unchanged in the urine.
e. Phenytoin concentration monitoring is best performed
using collection of blood in a serum separator tube.

Answer 2

a. Phenytoin exhibits zero-order kinetics with saturation
of metabolism at conventional doses.

Question 3

3. Which of the following best describes drug therapy with aminoglycosides?

a. The risk for ototoxicity with gentamicin is best correlated with serum trough concentration.
b. The risk of nephrotoxicity induced by amikacin is best
correlated with peak drug concentration.
c. Aminoglycoside dosing should be adjusted for patients
with renal insufficiency.
d. Aminoglycoside dosing should be adjusted for patients
with liver dysfunction.
e. Once daily (extended interval) dosing of aminoglycoside antibiotics is frequently used in patients with endstage renal failure.

Answer 3

c. Aminoglycoside dosing should be adjusted for patients
with renal insufficiency.

Question 4

4. Which of the following statements regarding therapeutic
   range are TRUE?

a. A therapeutic range is the range of drug concentrations
in which patients will respond to therapy.
b. A therapeutic range is the range of drug concentrations
in which the probability of efficacy is maximized and the probability of toxicity is minimized.
c. The concentration of a drug should not exceed its
therapeutic range because patients will develop toxicity.
d. Therapeutic ranges are always validated in randomized prospective trials of therapeutic drug monitoring.
e. The therapeutic range of a drug is unaffected by other
drugs used in combination and can therefore be
applied to all situations in which a drug is used

Answer 4

b. A therapeutic range is the range of drug concentrations
in which the probability of efficacy is maximized and the probability of toxicity is minimized.

Question 5

5. Which of the following best describes digoxin use and
   monitoring?
   a. The time of blood collection for digoxin does not affect
   interpretation of digoxin concentration.
   b. Digoxin is a mainstay of heart failure treatment due to
   its calcium channel–blocking effects.
   c. Digoxin absorption is very consistent across different
   formulations.
   d. Digoxin is frequently used to treat atrioventricular
   (AV) nodal dysfunction due to its enhancing effects
   on sympathetic nervous system activity within the
   heart.
   e. The measurement of digoxin concentrations can be
   affected by prior administration of Digibind (Digoxin
   Immune Fab).

Answer 5

e. The measurement of digoxin concentrations can be
affected by prior administration of Digibind (Digoxin
Immune Fab).