Hypokalemia means low blood potassium levels. Your body needs potassium to function correctly. It gets potassium through the food you eat. Hypokalemia is often caused by an excessive loss of potassium in your digestive tract due to vomiting, diarrhea or laxative use. Other causes include certain medications and some adrenal and genetic conditions.
Hypokalemia is when the amount of potassium in your blood is too low. Normal levels of potassium for an adult range from 3.5 to 5.2 mEq/L (3.5 to 5.2 mmol/L). Anything lower than 3 mEq/L (3 mmol/L) may be considered severe hypokalemia.
Potassium is an electrolyte. Electrolytes are minerals that carry an electric charge when they’re dissolved in your bodily fluids. Your body needs potassium for your cells, muscles and nerves to function correctly. Your body gets potassium through the food you eat. Your kidneys remove excess potassium through your urine (pee) to keep a proper balance of the mineral in your body.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
You need potassium to keep your muscles, nerves and heart working well. You also need potassium for a healthy digestive system and bone health. Low levels of potassium can affect these important functions in your body. Over time, low levels of potassium in your body can cause effects such as abnormal heart rhythms, muscle weakness and even paralysis.
Low blood potassium typically occurs because of an excessive loss of potassium in your digestive tract. This may be due to frequent vomiting, diarrhea or laxative use. Other causes of hypokalemia include:
Mild cases of low potassium may not cause any symptoms. But signs may include:
More severe cases of low potassium may cause signs and symptoms such as:
Your healthcare provider will check your potassium level through a blood test. The normal potassium level for an adult ranges from 3.5 to 5.2 mEq/L (3.5 to 5.2 mmol/L). Potassium levels between 3 and 3.5 mEq/L (3 to 3.5 mmol/L) are considered mild hypokalemia. Anything lower than 3 mEq/L (3 mmol/L) is considered severe hypokalemia.
Your healthcare provider may also order a basic or comprehensive metabolic panel. This panel is a group of blood tests that determine your body's kidney function and electrolyte balance.
If hypokalemia is confirmed, your healthcare provider will try to determine the cause. If the cause isn’t clear, they may order a urine test (urinalysis) to measure the amount of potassium in your urine.
Your healthcare provider may also order an electrocardiogram (ECG or EKG). An ECG measures your heart rhythm. Hypokalemia can cause abnormal heart rhythms. An ECG can pick up the abnormal heart rhythms.
If you have a mild case of hypokalemia, your healthcare provider will prescribe a potassium supplement that you’ll take by mouth. If your case is more severe, your healthcare provider may give you potassium through your vein (intravenously). Reasons you may need potassium through your vein include:
Your healthcare provider will also treat any condition that’s causing hypokalemia.
If you need to take a diuretic, your healthcare provider may switch you to a type that keeps potassium in your body. They may also tell you to take extra potassium supplements.
You can reduce your risk of developing hypokalemia by eating a diet full of foods that contain potassium. Discuss your diet with your healthcare provider. Foods that contain potassium include many fruits and vegetables, lean meat and fish, dairy and legumes. Foods that have lots of potassium include:
If you’re experiencing vomiting and diarrhea that lasts for more than 24 to 48 hours, you should get immediate medical care. The loss of fluid can cause hypokalemia. The sooner you seek treatment, the better your chances of preventing it.
(Note: If you’ve never had hypokalemia, prevention efforts aren’t usually necessary.)
If you have a mild case of hypokalemia, potassium supplements should help treat it. Make sure to continue eating a diet rich in potassium.
If your case is more severe, potassium given through your vein should treat it. If left untreated, severe hypokalemia can cause serious heart rhythm problems. In addition, life-threatening paralysis may occur.
Be sure to follow up with your healthcare provider to ensure that your hypokalemia is treated appropriately.
A note from Cleveland Clinic
When you have hypokalemia, the amount of potassium in your blood is too low. Your body needs potassium to function correctly. Hypokalemia can affect your cells, muscles, nerves, digestive system and skeletal system. To ensure you have enough potassium, work with your healthcare provider to make sure you’re eating enough foods that contain the mineral. And if you’ve been vomiting or experiencing diarrhea for more than one to two days, get medical care right away.
Last reviewed by a Cleveland Clinic medical professional on 05/10/2022.
Learn more about our editorial process.