Potassium is a mineral found in almost all foods. Your body needs some potassium to make your muscles work, but too much potassium can be dangerous. Having too much potassium in your blood is called hyperkalemia. When you are on dialysis, your potassium level may be too low or too high. Having too little or too much potassium can cause muscle cramps, weakness and irregular heartbeat. Having too much potassium can cause a heart attack. Ask your dietitian how much potassium you should have each day. Print and use this potassium log to keep track of how much potassium you take in!