Which patient history is a contraindication for acetazolamide?

Which patient history is a contraindication for acetazolamide?

• A. History of kidney stones
• B. Hypertension
• C. Asthma
• D. Myopia

Answer: (A)

Acetazolamide inhibits carbonic anhydrase in the proximal tubule, which reduces bicarbonate reabsorption and makes urine more alkaline. This alkaline urine increases the risk of calcium phosphate stone formation, so a patient with a history of kidney stones has a higher chance of stone recurrence and is considered a contraindication. Hypertension, asthma, and myopia do not carry the same stone-related risk with this drug. (Note: a known sulfonamide allergy is a separate precaution, but not shown among the options.)

Acetazolamide inhibits carbonic anhydrase in the proximal tubule, which reduces bicarbonate reabsorption and makes urine more alkaline. This alkaline urine increases the risk of calcium phosphate stone formation, so a patient with a history of kidney stones has a higher chance of stone recurrence and is considered a contraindication. Hypertension, asthma, and myopia do not carry the same stone-related risk with this drug. (Note: a known sulfonamide allergy is a separate precaution, but not shown among the options.)