Chloride is a type of electrolyte. It works with other electrolytes such as potassium, sodium, and carbon dioxide (CO2) to help keep the proper balance of body fluids and maintain the body's acid-base balance.
This article discusses the laboratory test to measures the amount of chloride in the fluid portion (serum) of the blood.
A blood sample is needed. For information on how this is done, see: Venipuncture.
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
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Drugs that may lower serum chloride measurements include:
Aldosterone
Bicarbonate-containing compounds
Loop diuretics
Thiazide 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 basic or comprehensive metabolic panel.
Normal Values
A typical normal range is 96 - 106 milliequivalents per liter (mEq/L).
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.
What abnormal results mean
A greater-than-normal level of chloride is called hyperchloremia. It may be due to:
Bromide poisoning
Carbonic anhydrase inhibitors (used to treat glaucoma)
There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
Excessive bleeding
Fainting or feeling light-headed
Hematoma (blood accumulating under the skin)
Infection (a slight risk any time the skin is broken)
References
DuBose TD Jr. Disorders of acid-base balance. In: Brenner BM, ed. Brenner and Rector's The Kidney. 8th ed. Philadelphia, Pa: Saunders Elsevier;2008:chap 14.
Review Date:
6/1/2011
Reviewed By:
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
