Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I understand your concern.

As you already seem to know Lasix is a medication to enhance diuresis. He does that by acting on kidney tubules and changing excretion and absorption of water and electrolytes. There are other medication with similar use but the trouble is that they all act on water and electrolyte metabolism thus you do not escape the potential side effects. Also not all of them have a quick powerful effect required for acute kidney failure. Otherwise there are not other alternatives apart from dialysis.

However I do not really think you are seeing this from the right angle. I do not think Lasix is necessarily the cause for the worsening of dementia. True it can disrupt electrolyte balance, but the kidney failure does as well, influences it even more actually. So I think the worsening is more probably due to kidney failure than Lasix. So the management should consist in monitoring electrolyte level (Na, K, Cl, pH) and water balance and correcting these abnormalities. It is them which worsen dementia (whether from kidney failure or lasix).

I remain at your disposal for further questions.

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