A 12 hours gap is the best strategy for the lasix (taking it like 9 Am and 9 PM). An increase in dose (starting the third) should not be done without your physician's advice as it can cause electrolyte abnormalities. Your physician is the best judge in this respect, as he knows your ejection fraction of heart (important in congestive heart failure), other blood investigation and concomitant illness. A fluid built up do warrant talking to your physician and he may consider giving you another medication like digitalis.
Please feel free for your follow up questions.
Digitalis would be addition to 320 mg of lasix. This is a prescription medication. Lasix is not discontinued.
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