PSA Renal and Hepatic Prescribing 3

Question 1

Which anticoagulant is generally preferred for a patient with severe renal impairment (CrCl <15 mL/min) requiring long-term anticoagulation?

Accepted Answer

Warfarin

Answer

Direct oral anticoagulants (DOACs) are substantially renally excreted and accumulate dangerously in severe renal impairment; warfarin, being hepatically metabolized, is preferred.

Question 2

Spironolactone is generally contraindicated in patients with severe renal impairment (eGFR <30 mL/min) primarily due to the risk of:

Accepted Answer

Life-threatening hyperkalemia

Answer

Spironolactone blocks aldosterone-mediated potassium excretion; in renal impairment, already-reduced potassium clearance combined with this effect causes dangerous hyperkalemia.

Question 3

In hepatic impairment, which plasma protein is most significantly reduced, leading to increased free drug fractions of highly protein-bound medications?

Accepted Answer

Albumin

Answer

Albumin, synthesized by the liver, is reduced in hepatic impairment, increasing the free fraction of acidic drugs like phenytoin, warfarin, and furosemide.

Question 4

A patient with severe hepatic impairment requires analgesia for moderate pain. Which approach is most appropriate?

Accepted Answer

Low-dose paracetamol (500mg TDS) with careful monitoring

Answer

Low-dose paracetamol with monitoring is safer than NSAIDs (GI bleeding and renal risk in cirrhosis) or opioids (risk of precipitating hepatic encephalopathy).

Question 5

Which antibiotic is almost entirely renally excreted and requires the most significant dose reduction when CrCl falls below 30 mL/min to prevent nephrotoxicity and ototoxicity?

Accepted Answer

Gentamicin

Answer

Gentamicin is almost entirely renally excreted unchanged; dose reduction and interval extension are essential in renal impairment to prevent nephrotoxicity and ototoxicity.

(PSA) Prescribing Safety Assessment Practice Test

(PSA) Prescribing Safety Assessment Practice Test

PSA Renal and Hepatic Prescribing 3