What is it?

A chloride test measures the level of chloride in your blood. Chloride is one of the most important electrolytes in the blood. It helps keep the amount of fluid inside and outside of your cells in balance. It also helps maintain proper blood volume, blood pressure, and the pH of your body fluids. Most of the chloride in your body comes from the salt (sodium chloride) you eat.

Why is this test done?

A test for chloride may be done to:

• Check your chloride level if you are having symptoms such as muscle twitching or spasms, breathing problems, weakness, or confusion.
• Find out whether you have kidney or adrenal gland problems.

How do you prepare for the test?

In general, there's nothing you have to do before this test, unless your doctor tells you to.

How is the test done?

A health professional uses a needle to take a blood sample, usually from the arm.

What happens after the test?

• You will probably be able to go home right away.
• You can go back to your usual activities right away.