Can Low Potassium Levels Cause Dizziness?

Have you ever felt dizzy or lightheaded? Sometimes the explanation is simple. You’re a bit dehydrated and need to drink more water. Or you were sitting for a long time and stood up too fast. 

But dizziness can be a sign of other medical conditions like hypokalemia (low potassium). Potassium plays a role in nearly every body function, including blood pressure control. When potassium levels fall, people can experience dizziness along with other symptoms. 

What does potassium do in the body? 

Potassium is an important mineral. It’s also called an electrolyte. That means it’s a mineral with an electrical charge. Potassium helps with many bodily functions, including:

• Maintaining fluid balance inside and outside cells        

• Allowing muscles to contract (including the heart muscle)      

• Helping nerves communicate with each other      

• Keeping blood pressure within a normal range

Getting enough potassium has been linked to better heart and bone health. It may also lower the risk of developing kidney stones.

Potassium levels can be measured with a blood test. Normal potassium levels run from 3.5 mEq/L to 5.5 mEq/L. But many people won’t have any symptoms unless their potassium falls below 3 mEq/L.  

Can low potassium make you dizzy?

Yes. Dizziness can be a sign of potassium deficiency or low potassium levels.

A sudden drop in potassium levels may affect the electrical activity of the heart. This can trigger an abnormal heart rhythm (arrhythmias), especially in people with a history of heart disease. If the heart isn’t beating correctly, oxygen can’t get to the brain. That makes people feel dizzy and lightheaded. Some people can even faint. 

Very low potassium levels can also cause severe muscle weakness and make it difficult to breathe. This also affects how much oxygen reaches the brain and can make people feel dizzy. 

Another more common reason people can get dizzy from low potassium levels has to do with dehydration. Stomach bugs (gastroenteritis) that cause vomiting and diarrhea can lead to both dehydration and low potassium levels. Dehydration can also cause dizziness. 

What are the other symptoms of low potassium ? 

Low potassium can cause other symptoms, too. Some other signs of low potassium can include: 

• Muscle weakness

• Muscle twitching

• Heart palpitations

• Fatigue

• Constipation

• Numbness or tingling in the hands and feet

The body works very hard to keep potassium levels in just the right range. If you take in too much potassium from your diet, your body removes the excess. If you take in too little, your body works hard to hold on to as much potassium as possible. 

But some medical conditions and medications can block this balance and cause a potassium deficiency. You may be at risk for developing hypokalemia if you:

• Take medications that can lower potassium levels like diuretics (water pills), laxatives, and insulin 

• Receive dialysis to treat chronic kidney disease

• Have Crohn’s disease, ulcerative colitis, or any condition that causes chronic diarrhea

• Have alcohol use disorder

How can you increase your potassium levels?

The best way to keep your potassium levels in a healthy range is to eat and drink potassium-rich foods. Some excellent sources of potassium include:

• Avocados

• Lentils

• Dried fruits like raisins and apricots

• Beans

• Potatoes

• Coconut milk

Most people won’t need to take potassium supplements. They can maintain normal potassium levels by adjusting their diet. 

If you do need to take potassium supplements, make sure to follow all dosing instructions and to follow up with your healthcare provider. You’ll need blood work to measure your potassium levels to make sure you don’t develop high potassium levels (hyperkalemia).   

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Written by:

Brian Clista, MD

Dr. Clista is a board-certified pediatrician who works in private practice in Pittsburgh, Pennsylvania. He previously served as a National Health Service Corporation Scholar in the inner city of Pittsburgh for 11 years.

Edited by:

Patricia Pinto-Garcia, MD, MPH

Patricia Pinto-Garcia, MD, MPH, is a medical editor at GoodRx. She is a licensed, board-certified pediatrician with more than a decade of experience in academic medicine.

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