Definition of Serum chloride:

Chloride is a negatively charged molecule known as an electrolyte. It works with other electrolytes, such as potassium, salt (sodium), and carbon dioxide (CO2), to help keep the proper balance of body fluids and maintain the body's acid-base balance.

The serum chloride test measures the amount of chloride in the fluid portion of the blood.

See also:

• Chloride in diet
• Chloride - urine test
• Sweat chloride test
• Urine electrolytes test

How the test is performed:

Blood is drawn from a vein or capillary. A laboratory machine spins the blood to separate the cells from the serum, and the level of chloride in the serum is measured.

How to prepare for the test:

Your doctor may tell you to temporarily stop taking certain drugs that can affect test results.

Drugs that may increase serum chloride measurements include:

• Acetazolamide
• Ammonium chloride
• Androgens
• Cortisone
• Estrogen
• Guanethidine
• Methyldopa
• Non-steroidal anti-inflammatory drugs (NSAIDs)

Drugs that may lower serum chloride measurements include:

• Aldosterone
• Bicarbonates
• Certain diuretics
• Triamterene

Never stop taking medication without first talking to your doctor.

Why the test is performed:

Your doctor may order this test if you have signs of a disturbance in your body's fluid level or acid-base balance.

This test is usually ordered along with other blood tests such as a metabolic panel (CHEM-7 or CHEM-20).