6 Flashcards
(10 cards)
Which psychoactive drug requiring TDM is used for mood stabilization?
Lithium carbonate, due to its narrow therapeutic window and risk of renal toxicity.
Why is Cyclosporine monitored in transplant patients?
Because Cyclosporine has a narrow therapeutic index and can cause nephrotoxicity; dosing is complicated by variable absorption and metabolism.
What anti-neoplastic agent commonly undergoes TDM and why?
Methotrexate, since it inhibits DNA synthesis and can cause severe toxicity if plasma levels are too high; clearance varies with renal function.
How long after a single marijuana use can THC metabolites be detected in urine?
Approximately 3–5 days, using GC/MS methods.
Which analytical techniques are used to detect amphetamines in body fluids?
Liquid chromatography (LC) and gas chromatography (GC).
Why are anabolic steroids monitored in athletes?
Because they can enhance muscle mass and performance; illicit use is detected via GC or GC/MS in urine.
What are common methods to detect opioids in suspected abuse cases?
Gas chromatography–mass spectrometry (GC/MS) assays of urine or blood.
In a TDM context, why is sampling time critical when measuring trough levels?
Because sampling immediately before the next dose ensures the lowest steady-state concentration is measured, reflecting true maintenance dosing.
How does renal hemofiltration affect drug clearance and the need for TDM?
Hemofiltration can increase elimination of renally cleared drugs, necessitating dose adjustments and close TDM to maintain therapeutic levels.
What key information must be considered to interpret Amiodarone levels correctly?
Patient’s dosing history, time since last dose (half-life ~50 days), concurrent medications, and liver/thyroid function, since Amiodarone distributes extensively and has complex metabolism.
