Aminoglycoside renal monitoring — GPhC CRA MCQ

Correct answer: B — Verify indication, dosing weight, CrCl, dose times and level plan

Verify indication, dosing weight, CrCl, dose times and level plan: Safe extended-interval gentamicin use requires a coherent indication and regimen, an appropriate dosing weight, renal function, known administration times and correctly timed concentration monitoring. Verify indication, actual weight, eGFR, intended duration and a late peak: Actual weight and eGFR may not be the required dosing variables, and an isolated late peak does not establish the prescribed extended-interval plan. Verify dosing weight, CrCl, dose interval, trough plan and allergy status: A level cannot be interpreted safely without the indication, regimen and exact administration time. Verify indication, serum creatinine, treatment duration, culture and fluid balance: Serum creatinine alone and a later culture do not control current exposure or aminoglycoside accumulation. Verify inflammatory markers, eGFR, ototoxicity history, duration and allergy status: Those data may inform review but cannot validate the interval or permit interpretation of a serum concentration.

Reference: BNF: gentamicin: https://bnf.nice.org.uk/drugs/gentamicin/; MHRA: use creatinine clearance for medicines requiring renal dose adjustment: https://www.gov.uk/drug-safety-update/prescribing-medicines-in-renal-impairment-using-the-appropriate-estimate-of-renal-function-to-avoid-the-risk-of-adverse-drug-reactions