Chloride Blood Test

A chloride blood test measures the amount of chloride in your blood. Chloride is a type of electrolyte. Electrolytes are electrically charged minerals that help control the amount of fluids and the balance of acids and bases (pH balance) in your body.

You have electrolytes in your blood, urine, tissues, and other body fluids. You get chloride through the food you eat. It is mainly found in salt.

Your body gets rid of the extra chloride in your urine (pee). Chloride helps control the amount of fluid in your body. In addition, it helps maintain healthy blood volume and blood pressure.

Many diseases and other factors can cause abnormal chloride levels. Chloride is often measured with other electrolytes to diagnose or monitor conditions such as kidney disease, heart failure, liver disease, and high blood pressure.

Why this test is done

Your health care provider may have ordered a chloride blood test as part of an electrolyte panel, a routine blood test that measures chloride and other electrolytes, such as potassium, sodium, and bicarbonate.

You may also need a chloride blood test if you have symptoms of an acid or fluid imbalance, including:

• Vomiting over a long period of time
• Diarrhea
• Fatigue
• Weakness
• Dehydration
• Trouble breathing

How to prepare

You may need to stop taking certain medicines before this test, so tell your provider about everything you take. But don't stop taking any medicines unless your provider tells you to.

If your provider has ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test. Your provider will let you know if there are any special instructions.

Sample type

Blood

Other names for this test

CI, Serum chloride