Chloride

Does this test have other names?

Cl, serum chloride test

What is this test?

This test will find out how much chloride is in your blood and help your healthcare provider figure out if you may have certain kidney problems, lung disorders, or problems in other systems that regulate the acid-base balance in your body.

Chloride is one of the ingredients in table salt. But it's also an important mineral in your body. It helps move fluids in and out of your blood cells. When you have an imbalance of chloride, you may start to feel ill. You can lose chloride if you've been vomiting or have diarrhea. Chloride can also build up if you have a certain type of diabetes, kidney disease, or metabolic acidosis (a condition in which you have too much acid in your blood).

You can lose chloride if you've been vomiting over a prolonged period or have diarrhea, weakness, dehydration, excessive sweating, difficulty in breathing, metabolic alkalosis (a condition in which you have too much base in your blood), or excess water gain, such as in congestive heart failure.

Why do I need this test?

You may need this test if you have nausea, feel weak, or become seriously dehydrated, causing you to lose too much chloride.

This test may help your health care provider find out if your kidneys are working correctly or if you have another problem with your health.

What other tests might I have along with this test?

You may also need a test to measure the other electrolytes in your blood. The electrolytes test will measure other minerals in your blood, including sodium and potassium. This test can also help to check for an acid-base imbalance.

You may also need to have your urine tested for chloride levels and your blood for glucose, or blood sugar, levels. A basic urinalysis may also be done. This is a simple test that may help find problems with your kidneys or urinary tract. Two other tests may be done to see how well your kidneys are working. These 2 tests are for creatinine and blood urea nitrogen levels.

What do my test results mean?

Test results may vary depending on your age, gender, health history, and other things. Your test results may be different depending on the lab used. They may not mean you have a problem. Ask your healthcare provider what your test results mean for you.

Here are the normal ranges:

• For adults: 96 to 106 milliequivalents per liter (mEq/L*)

• For children: 95 to 108 mEq/L*

• For newborn babies: 96 to 113 mEq/L*

How is the test done?

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

You may also have to give a urine sample for testing.

Does this test pose any risks?

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore.

What might affect my test results?

The amount of fluid you drink or lose may affect your test results. If you've been vomiting or have lost fluids because of diarrhea, or excessive sweating you may have lower levels of chloride.

Some fluids, such as drinks with caffeine, may cause water loss or bloating and affect the chloride you have in your body.

How do I get ready for this test?

You don't need to do anything to get ready for this test. Be sure your health care provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illegal drugs you may use. Your provider may ask you to temporarily stop taking certain medicines that can interfere with the test’s results.