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Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• What is is potassium?
• What are the causes of low potassium (hypokalemia)?
• What are the symptoms of low potassium?
• How is low potassium diagnosed?
• What is the treatment for low potassium?
• How can low potassium be prevented?
• Patient Comments: Low Potassium (Hypokalemia) - Diagnosis
• Patient Comments: Low Potassium - Symptoms and Signs
• Find a local Internist in your town
• Low Potassium (Hypokalemia) Index

Potassium affects the way neuromuscular cells discharge energy (depolarize) and then regenerate (repolarize) that energy to be able to fire again. When potassium levels are low, the cells cannot repolarize and are unable to fire repeatedly, so the  muscles and nerves can function normally. The effects of low potassium include can cause the following symptoms:

• muscle weakness,
• muscle aches,
• muscle cramps, and
• palpitations (irregular heartbeats).

Potassium levels in the blood may be easily measured by routine blood tests.

Low potassium is often a potential complication of medication, for example, patients with high blood pressure who are being treated with diuretics such as hydrochlorothiazide (Hydrodiuril) or furosemide (Lasix) often have their potassium levels monitored.

Patients who become ill with vomiting and diarrhea, may develop dehydration and weakness. Part of the patient evaluation may include having their electrolyte levels tested in order to determine whether body potassium losses may need to be replaced.

There can be electrocardiogram (EKG, ECG) changes associated with low potassium, and sometimes the diagnosis of low potassium is made incidentally by finding the characteristic "U" waves on the EKG tracing. In severe cases, hypokalemia can lead to dangerous disturbances in heart rhythm (dysrhythmia).