Which statement about probenecid in gout management is correct?
- A It inhibits xanthine oxidase and reduces urate formation
- B It is a uricosuric agent that should not be initiated during an acute gout attack and loses efficacy when creatinine clearance falls below about 50 mL/min ✓
- C It converts uric acid to the more soluble allantoin
- D It increases tubular reabsorption of urate through URAT1 activation
Correct answer: B. It is a uricosuric agent that should not be initiated during an acute gout attack and loses efficacy when creatinine clearance falls below about 50 mL/min
Explanation
Probenecid blocks reabsorption of urate at the proximal tubule by inhibiting transporters including URAT1, promoting urinary excretion. Initiating it during an acute flare shifts urate loads and can worsen or prolong the attack, and because secretion of probenecid itself depends on renal function, it becomes ineffective once creatinine clearance drops below roughly 50 mL/min. Xanthine oxidase inhibition defines allopurinol and febuxostat, while allantoin conversion is the action of uricase enzymes such as pegloticase.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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