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Date of last update: 10/20/2017.

Forum Name: Miscellaneous Cardiology Topics

Question: Is the relationship between Lasix and Potassium Linear?

 FloydV - Tue Apr 28, 2009 12:35 pm

I take 80 mg of lasix a day. I also take 120 MeQ of potassium per day, 40 of which must be liquid. So, that is 60 MeQ per 40 mg of lasix. The question is: Is the relationship linear. If I take an additional 40 mg of lasix does an extra 60 MeQ (for a total of 180 MeQ) seem right? I know the quantity seems high, but it has been confirmed many times and keeps my K level at 4.2 to 4.3 which is necessary, because of the Tikosyn.
 John Kenyon, CNA - Mon May 04, 2009 10:58 pm

User avatar Hi there --

The relationship between potassium and Lasix is theoretically linear, but in practice it doesn't necessarily work that way. There are too many metabolic variables. However, for a given individual the relationship should remain relatively stable, and it is especially important to keep your K level in the low-to-mid 4s range as you've mentioned. If 180 meq does this without any evidence of hyperkalemia (which is every bit as dangerous as hypo-K), then if it works for you, you've found the right combination. You cannot, however, boost it or fine tune it on a day-to-day basis, and it must be treated as though it is a linear relationship in order to avoid hyper-K situations. You'll need to confirm this with your doctor, and not add K on your own, because you have no ready method to monitor it. If you've found a working correlation between it and Lasix then you should stay with this until and unless you've discussed this with your doctor, who's interest is also in keeping things fairly level. It's not realistic to expect it to stay linear at all times,even though the theory works that way. In practice it rarely works out that way.

Hope this is helpful. Good luck to you and please follow up with us here as needed.

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