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Im having trouble understanding Acetazolamide
I know it blocks Carbonic Anhydrase
Resulting in:
Increased Na Loss in urine
Increased HCO3 Loss in urine
Why is there a hypokalemia?
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Whenever you have increased urine output, it's like flushing the nephrons with water and thus K would be flushed as well. So K is lost in the urine.
But remember you're losing HCO3 from the serum ==> acidemia ==> hyperkalemia as it's being shifted from inside the cells into the serum.
In general, the total body K is less, but the serum K could be normal or elevated.
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I understand this, yet the literature always mentions a side effect as being Hypokalemia, and not Hyperkalemia... that's where im a little confused.
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MOST OF SODIUM EXCRETED IN PROX. TUBULE (LARGE CONC.)SHOULD BE REABSORB. IN DISTAL TUBUL,,,,THIS WILL BE IN EXCHANGE OF POTASIUM,,,, LEAD TO HYPOKALEMA,,,,,,BEST REGARDS
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Due to CA enzyme inhibition H+ is not buffered by Hco3- in PCT lumen and neither of them are generated inside the PCT cells. Upon reaching the collecting duct, due to increased load of H + in tubular lumen H+/K+ antiport is less functional. So there is reduced K+ absorption and therfore hypokalemia
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acetazolamide increases HCO3 excretion. your body get it as an approaching acidosis, so the kidney start increase H reabsorption which happens in exchange with K,