PSA PSA Therapeutic Drug Monitoring 1

Question 1

Which of the following drugs requires routine therapeutic drug monitoring (TDM) due to its narrow therapeutic index?

Accepted Answer

Vancomycin

Answer

Vancomycin has a narrow therapeutic index and requires routine TDM to ensure efficacy and prevent nephrotoxicity.

Question 2

A patient on digoxin has a serum level of 2.8 ng/mL. The therapeutic range is 0.5–2.0 ng/mL. What is the most appropriate next step?

Accepted Answer

Hold digoxin and reassess

Answer

A digoxin level above the therapeutic range indicates toxicity risk; the dose should be held and the patient reassessed for signs of toxicity.

Question 3

When should a trough level for vancomycin be drawn to accurately reflect steady-state concentrations?

Accepted Answer

Immediately before the next dose

Answer

Vancomycin trough levels should be drawn immediately before the next scheduled dose to reflect the lowest steady-state concentration.

Question 4

Which pharmacokinetic parameter is most important when interpreting TDM results for aminoglycosides?

Accepted Answer

Peak and trough levels

Answer

For aminoglycosides, both peak (efficacy) and trough (toxicity avoidance) levels are monitored to optimize dosing.

Question 5

A patient on phenytoin has a total level of 8 mcg/mL (therapeutic 10–20 mcg/mL) but appears clinically stable. Their albumin is 2.0 g/dL. What should you consider?

Accepted Answer

Check free phenytoin level before adjusting

Answer

Phenytoin is highly protein-bound; low albumin increases the free fraction, so a corrected or free phenytoin level is needed before adjusting the dose.

(PSA) Prescribing Safety Assessment Practice Test

(PSA) Prescribing Safety Assessment Practice Test

PSA PSA Therapeutic Drug Monitoring 1