No , the Lasix
is not the cause, in fact Lasix makes you lose potassium in the urine, for that reason we often have to ad potassium when patients are on Lasix. Your high potassium levels are probably due to your kidney
damage. It can also be due to increased intake, or certain medication which hold back potassium in the kidney. These are usually a different class of diuretics (potassium sparing diuretics) an example being Aldosterone
. Perhaps you were treated with these during your kidney failure. Ask your doctor about this.