Potassium is an essential mineral that your body needs for many functions. Having too much potassium in your body or having too little can both be dangerous to your health. If you’re concerned that your potassium levels are too low, consult your doctor about the treatment that’s right for you.

Function

You can get potassium in your diet from many fruits and vegetables, as well as milk and beans, according to the University of Michigan Health System. Meats and many kinds of fish contain potassium as well. Potassium helps control the water in your body and your blood pressure. The mineral also acts as an electrolyte and controls electrical impulses in your body, particularly in your heart and muscles, according to the University of Maryland Medical Center. Your sodium and magnesium blood levels control your potassium levels.

Causes

A low potassium level in your blood is known as hypokalemia, says the University of Maryland Medical Center. You can have a potassium deficiency due to excessive sodium intake, malnutrition, vomiting or diarrhea, or Crohn’s disease and other conditions that inhibit your absorption of nutrients. You can also develop a potassium deficiency from taking loop diuretics for heart problems. Potassium deficiencies are somewhat common among people who consume Western diets, due to the high amount of sodium consumed, according to the University of Pittsburgh Medical Center.

Symptoms

If your potassium levels become too low, you might experience symptoms like constipation, fatigue or weakness and heart arrhythmias, the Mayo Clinic says. Because these symptoms are easy to confuse with other health conditions, most people don’t realize that they have low potassium levels until their health-care provider performs a blood test. Extremely low potassium levels can potentially become fatal.

Effects

Low potassium levels in your blood can cause blood pressure problems, so potassium supplements are sometimes recommended for people with hypertension, says the University of Pittsburgh Medical Center. Dozens of medical studies have found that taking potassium supplements reduced blood pressure in hypertensive patients, according to a 1997 review of clinical trials in the Journal of the American Medical Association. Potassium supplementation may also help in treating kidney stones and premenstrual syndrome, as well as cardiovascular problems like congestive heart failure, stroke and cardiac arrhythmia, says the University of Michigan Health System. People with malabsorption conditions like inflammatory bowel disease, Crohn’s disease or ulcerative colitis might also benefit from taking a potassium supplement, according to the University of Maryland Medical Center. Talk with your doctor before taking potassium to treat or prevent any health condition.

Treatment

If you have a potassium deficiency, you might take 10 to 20 milliequivalents three to four times daily, says the University of Pittsburgh Medical Center. You may also need to take magnesium and vitamin B12 supplements along with potassium. Ask your physician about the dosage that’s right for you before taking a potassium supplement, however. Your doctor might advise against taking potassium if you’re also taking ACE inhibitors like Monopril or Capoten, the blood-thinner heparin, cyclosporine, beta-blockers like Inderal or Lopressor, and certain antibiotics like Bactrim, according to the University of Maryland Medical Center. Also, if you have impaired kidney function, taking potassium supplements might not be safe, especially if you’re also taking nonsteroidal anti-inflammatory drugs.