My potassium level is 5.4. is this high? my doctor wants me to get an ecg

High potassium: ECG always good idea if you have high potassium. But 1st thing to do is repeat the lab test, since often tube is left out for too long or delayed in testing and blood cells lyse (break open) and spill potassium into the fluid in the tube causing falsely elevated potassium.

High potassium: I agree with Dr. B. Also be aware that certain blood pressure medications, a certain diuretic, potassium supplements, and kidney disorders especially with eating potassium rich foods can cause high serum potassium.