Renal and Hepatic Prescribing Flashcards
7 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 7 Renal and Hepatic Prescribing flashcards as text
A patient with CrCl 20 mL/min requires gentamicin therapy. What is the most appropriate dose adjustment strategy?
Answer: Reduce dose and extend the dosing interval
In renal impairment, aminoglycosides require dose reduction and extended dosing intervals to prevent accumulation and nephrotoxicity/ototoxicity.
Which of the following drugs does NOT typically require dose reduction in renal impairment?
Answer: Rifampicin
Rifampicin is primarily hepatically metabolized and excreted in bile, so it does not require dose reduction in renal impairment.
A patient with Child-Pugh Class C cirrhosis requires sedation. Which benzodiazepine is most appropriate?
Answer: Lorazepam
Lorazepam undergoes direct glucuronidation rather than hepatic oxidative metabolism, making it safer in severe liver disease where CYP450 activity is impaired.
Which opioid is considered relatively safest for analgesia in a patient with severe renal impairment (eGFR <15 mL/min)?
Answer: Fentanyl
Fentanyl is metabolized to inactive metabolites that are not significantly renally excreted, making it safer than morphine or codeine in severe renal impairment.
A patient with stage 4 CKD (eGFR 20 mL/min) is currently taking metformin for type 2 diabetes. What is the most appropriate action?
Answer: Stop metformin immediately
Metformin is contraindicated when eGFR falls below 30 mL/min due to the risk of potentially fatal lactic acidosis from drug accumulation.
Which of the following antihypertensives requires the greatest dose reduction in severe renal impairment compared to normal renal function?
Answer: Atenolol
Atenolol is almost entirely renally excreted unchanged, requiring significant dose reduction to prevent accumulation and bradycardia in renal impairment.
In hepatic impairment, what change occurs to the first-pass effect of orally administered drugs with high hepatic extraction ratios?
Answer: It is decreased, increasing oral bioavailability
Hepatic impairment reduces first-pass metabolism, allowing more of an orally administered high-extraction drug to reach systemic circulation, increasing bioavailability.