Will Potassium Sparing Diuretic Cause Fluctuations In Serum Potassium Levels?

Question : I has been getting palpitations and got blood drawn on thursday. I remember being asked to clench my fists as the nurse was finding it hard to get blood. On friday (24 hours later) I got a call from my doctor telling me my labs showed a serum k of 6 and that I was to avoid all potassium rich foods and supplements. I immefiately took myself to the ER where they retested the result was 3.5. Now my question is, without the opportunity to alter my diet, could serum k have fallen from. 6 to 3.5 in 24 hours? I know that there is a risk that due to fist clenching the first result was an error but is there a chance that it was accurate and fell natirally to 3.5 the next day? I am concerned becsuse i take a potassium sparing diuretic and i worry it is causing issues with my seum potassium levels. Thanks for your snswer.

So you are saying it's possible for serum potassium to fall in 24 hours from 6 to 3.5 without a change in diet or supplementation and there may not have been a lad error. The point of my question is to see how volatile my potassium is. Can it move so much is such a short time? Your other colleague said I would have been in intensive care with a k of 6 and you're saying it's not that high. I am very confused. How can I keep my potassium stable if it can jump from 3.9 to 6 to 3.5 with no kidney problems.