What is the mechanism of action for allopurinol and probenecid in gout management?

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Multiple Choice

What is the mechanism of action for allopurinol and probenecid in gout management?

Gout management can lower uric acid in two main ways: by reducing its production or by increasing its excretion. Allopurinol does the former by inhibiting xanthine oxidase, the enzyme that converts hypoxanthine and xanthine into uric acid. Slowing this step lowers the overall amount of uric acid produced. Probenecid does the latter by blocking the renal proximal tubule’s reabsorption of uric acid, so more uric acid is eliminated in the urine and serum urate levels fall. In practical terms, allopurinol helps prevent new crystal formation by cutting production, while probenecid helps clear existing urate by increasing urate junk-out through the kidneys.

Gout management can lower uric acid in two main ways: by reducing its production or by increasing its excretion. Allopurinol does the former by inhibiting xanthine oxidase, the enzyme that converts hypoxanthine and xanthine into uric acid. Slowing this step lowers the overall amount of uric acid produced. Probenecid does the latter by blocking the renal proximal tubule’s reabsorption of uric acid, so more uric acid is eliminated in the urine and serum urate levels fall.

In practical terms, allopurinol helps prevent new crystal formation by cutting production, while probenecid helps clear existing urate by increasing urate junk-out through the kidneys.

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