Overview of Electrolytes

Reviewed/Revised Feb 2023
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What are electrolytes?

Electrolytes are minerals that circulate in your blood. These minerals are also in your stomach juices, in your stool (poop), in your urine, and inside your body's tissues. Salt (sodium) is one example of an electrolyte. Others include potassium, calcium, magnesium, chloride, and bicarbonate.

Electrolytes help in many different body functions:

  • Controlling nerve and muscle function

  • Balancing the amount of water in your body

  • Balancing the acid level of your body

Your kidneys keep the right balance of electrolytes in your blood. Having too much or too little of an electrolyte can cause health problems.

What causes an electrolyte problem?

Your body can have an electrolyte imbalance if you:

  • Have a lot of vomiting (throwing up) and/or diarrhea (frequent, loose, or watery poop)

  • Sweat a lot on a hot day

  • Drink too much or too little water

  • Take certain medicines

  • Have certain heart, kidney, or liver diseases

What are the symptoms of an electrolyte problem?

You may have no symptoms. If you do have symptoms, they depend a lot on which electrolyte is out of balance. But in general you may:

  • Feel weak and tired

  • Have muscle cramps or twitching

  • Become confused

  • Have an irregular heartbeat

How do doctors know if I have an electrolyte problem?

Your doctor will do a blood test to see if you have an electrolyte problem.

How do doctors treat an electrolyte problem?

Your doctor will try to balance your electrolytes.

  • If you have too little of an electrolyte, you'll usually be given more of that electrolyte by mouth or in your veins (IV)

  • If you have too much of an electrolyte, you may get fluids by IV or a medicine to dilute it and help remove it from your body

Some serious electrolyte problems can require kidney dialysis (a treatment that drains blood out of your body, filters it, and returns it to your body).

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