PSA Therapeutic Drug Monitoring Flashcards
6 cards from real PSA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 PSA Therapeutic Drug Monitoring flashcards as text
A patient on theophylline for COPD has a level of 22 mcg/mL (therapeutic 10–20 mcg/mL). Which symptom is most consistent with theophylline toxicity?
Answer: Seizures
Theophylline toxicity can cause seizures, tachycardia, and arrhythmias, with seizures being a serious manifestation at supratherapeutic levels.
Which condition would most likely increase cyclosporine blood levels and require downward dose adjustment?
Answer: Co-administration of fluconazole
Fluconazole inhibits CYP3A4, reducing cyclosporine metabolism and increasing blood levels, necessitating dose reduction.
For patients on warfarin, INR is used as a surrogate for TDM. A patient with atrial fibrillation has an INR of 4.8 (target 2.0–3.0). What is the most appropriate action if there is no active bleeding?
Answer: Hold warfarin and recheck INR in 1–2 days
For a supratherapeutic INR without active bleeding, holding warfarin and rechecking in 1–2 days is the standard approach.
Which of the following best describes why TDM for tacrolimus uses whole blood rather than serum?
Answer: Tacrolimus concentrates extensively in red blood cells
Tacrolimus binds extensively to erythrocytes, making whole blood the appropriate matrix for accurate TDM.
A patient on methotrexate for rheumatoid arthritis has elevated liver enzymes. What monitoring parameter is specifically recommended to prevent methotrexate hepatotoxicity?
Answer: Liver function tests and CBC at regular intervals
Regular liver function tests and CBC are recommended for patients on methotrexate to detect hepatotoxicity and myelosuppression early.
When interpreting a gentamicin peak level drawn 30 minutes after a 30-minute infusion ends, the result is 14 mcg/mL (therapeutic peak 5–10 mcg/mL for traditional dosing). What is the most appropriate action?
Answer: Extend the dosing interval
A supratherapeutic peak with traditional aminoglycoside dosing warrants extending the dosing interval to allow adequate drug elimination and prevent toxicity.