Also Known As
Cl
Formal Name
Chloride
This article was last reviewed on
This article waslast modified on
January 15, 2018.
At a Glance
Why Get Tested?

To determine if there is a problem with your body's electrolyte balance or acid-base (pH) balance and to monitor treatment; as part of a routine health checkup

When To Get Tested?

As part of a standard electrolyte panel or metabolic panel or when your healthcare practitioner thinks that your signs and symptoms may be due to an electrolyte imbalance

Sample Required?

A blood sample drawn from a vein in your arm; sometimes a random or 24-hour urine sample

Test Preparation Needed?

None

You may be able to find your test results on your laboratory's website or patient portal. However, you are currently at Lab Tests Online. You may have been directed here by your lab's website in order to provide you with background information about the test(s) you had performed. You will need to return to your lab's website or portal, or contact your healthcare practitioner in order to obtain your test results.

Lab Tests Online is an award-winning patient education website offering information on laboratory tests. The content on the site, which has been reviewed by laboratory scientists and other medical professionals, provides general explanations of what results might mean for each test listed on the site, such as what a high or low value might suggest to your healthcare practitioner about your health or medical condition.

The reference ranges for your tests can be found on your laboratory report. They are typically found to the right of your results.

If you do not have your lab report, consult your healthcare provider or the laboratory that performed the test(s) to obtain the reference range.

Laboratory test results are not meaningful by themselves. Their meaning comes from comparison to reference ranges. Reference ranges are the values expected for a healthy person. They are sometimes called "normal" values. By comparing your test results with reference values, you and your healthcare provider can see if any of your test results fall outside the range of expected values. Values that are outside expected ranges can provide clues to help identify possible conditions or diseases.

While accuracy of laboratory testing has significantly evolved over the past few decades, some lab-to-lab variability can occur due to differences in testing equipment, chemical reagents, and techniques. This is a reason why so few reference ranges are provided on this site. It is important to know that you must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."

For more information, please read the article Reference Ranges and What They Mean.

Chloride Reference Range

The reference ranges1 provided here represent a theoretical guideline that should not be used to interpret your test results. Some variation is likely between these numbers and the reference range reported by the lab that ran your test. Please consult your doctor. 

Age Conventional Units2 SI Units3
0-18 years Not available due to wide variability. See child's lab report for reference range.
Adult 98-107 mEq/L 98-107 mmol/L
>90 years 98-111 mEq/L 98-111 mmol/L

1 from Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Burtis CA, Ashwood ER, Bruns DE, eds. 5th edition, St. Louis: Elsevier Saunders; 2011.

2 Conventional Units are typically used for reporting results in U.S. labs

3 SI Units are used to report lab results outside of the U.S.

What is being tested?

Chloride is an electrolyte. It is a negatively charged ion that works with other electrolytes, such as potassium, sodium, and bicarbonate, to help regulate the amount of fluid in the body and maintain the acid-base balance. This test measures the level of chloride in the blood and/or urine.

Chloride is present in all body fluids but is found in the highest concentration in the blood and in the fluid outside of the body's cells. Most of the time, chloride concentrations mirror those of sodium, increasing and decreasing for the same reasons and in direct relationship to sodium. When there is an acid-base imbalance, however, blood chloride levels can change independently of sodium levels as chloride acts as a buffer. It helps to maintain electrical neutrality at the cellular level by moving into or out of the cells as needed.

We get chloride in our diet through food and table salt, which is made up of sodium and chloride ions. Most of the chloride is absorbed by the digestive tract, and the excess is eliminated in urine. The normal blood level remains steady, with a slight drop after meals (because the stomach produces acid after eating, using chloride from blood).

How is the sample collected for testing?

A blood sample is taken by needle from a vein in the arm. Chloride can also be measured in a random or 24-hour urine sample.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.

Accordion Title
Common Questions
  • How is it used?

    A chloride blood test is used to detect abnormal concentrations of chloride. It is often ordered, along with other electrolytes, as part of a regular physical to screen for a variety of conditions.

    Chloride is an electrolyte. It is a negatively charged ion that works with other electrolytes, such as potassium, sodium, and bicarbonate, to help regulate the amount of fluid in the body and maintain the acid-base (pH) balance.

    Chloride and electrolyte tests may also be ordered to help diagnose the cause of signs and symptoms such as prolonged vomiting, diarrhea, weakness, and difficulty breathing (respiratory distress). If an electrolyte imbalance is detected, a healthcare practitioner will look for and address the disease, condition, or medication causing the imbalance and may order electrolyte testing at regular intervals to monitor the effectiveness of treatment. If an acid-base imbalance is suspected, the healthcare practitioner may also order tests for blood gases to further evaluate the severity and cause of the imbalance.

    In persons with too much base, urine chloride measurements can tell the healthcare practitioner whether the cause is loss of salt (in cases of dehydration, vomiting, or use of diuretics, where urine chloride would be very low) or an excess of certain hormones such as cortisol or aldosterone that can affect electrolyte elimination.

  • When is it ordered?

    The blood chloride test is almost never ordered by itself. It is usually ordered as part of an electrolyte panel, a basic metabolic panel, or a comprehensive metabolic panel, which are ordered frequently as part of a routine physical.

    Chloride, as part of an electrolyte or metabolic panel, may be ordered when acidosis or alkalosis is suspected or when someone has an acute condition with symptoms that may include the following:

    • Prolonged vomiting and/or diarrhea
    • Weakness, fatigue
    • Difficulty breathing (respiratory distress)

    Electrolytes may be ordered at regular intervals when a person has a disease or condition or is taking a medication that can cause an electrolyte imbalance. Electrolyte panels or basic metabolic panels are commonly used to monitor treatment of certain problems, including high blood pressure (hypertension), heart failure, and liver and kidney disease.

    A urine chloride test may be performed along with a blood or urine sodium when evaluating the cause of low or high blood chloride levels. A healthcare practitioner will look at whether the chloride measurement changes mirror those of the sodium. This helps the healthcare practitioner determine if there is also an acid-base imbalance and helps to guide treatment.

  • What does the test result mean?

    An increased level of blood chloride (called hyperchloremia) usually indicates dehydration, but can also occur with other problems that cause high blood sodium, such as Cushing syndrome or kidney disease. Hyperchloremia also occurs when too much base is lost from the body (producing metabolic acidosis) or when a person hyperventilates (causing respiratory alkalosis).

    A decreased level of blood chloride (called hypochloremia) occurs with any disorder that causes low blood sodium. Hypochloremia also occurs with congestive heart failure, prolonged vomiting or gastric suction, Addison disease, emphysema or other chronic lung diseases (causing respiratory acidosis), and with loss of acid from the body (called metabolic alkalosis).

    An increased level of urine chloride can indicate dehydration, starvation, Addison disease, or increased salt intake. If both chloride and sodium levels are high in a person on a restricted salt diet, the person is not complying with the diet.

    A decreased level of urine chloride can be seen with Cushing syndrome, Conn syndrome, congestive heart failure, malabsorption syndrome, and diarrhea.

  • Is there anything else I should know?

    Drugs that affect sodium blood levels will also cause changes in chloride. In addition, swallowing large amounts of baking soda or substantially more than the recommended dosage of antacids can also cause low blood chloride.

  • Are there dietary recommendations for chloride?

    Yes. The Food and Nutrition Board at the Institute of Medicine recommends that adolescents and adults ages 14 to 50 years consume 2.3 g/day. The recommendations vary based on age, sex, and other factors. Chloride is readily available in the food supply and most Americans probably consume more than necessary, in the form of table salt and salt in prepared foods. It is also found in many vegetables and in foods such as salted meats, butter, tomatoes, lettuce, celery, and olives.

  • What treatment is prescribed for abnormal chloride levels?

    The same treatment used to treat sodium imbalances (diuretics, fluid replacement) may be used to treat chloride imbalances.

View Sources

Sources Used in Current Review

Boggs, W. (2015 August 11). Serum Chloride Levels Predict Mortality in Acute Decompensated Heart Failure. Medscape Multispecialty [On-line information]. Available online at http://www.medscape.com/viewarticle/849010. Accessed 10/15/15.

Kamel, G. (2014 February 28, Updated). Chloride. Medscape Drugs & Diseases [On-line information]. Available online at http://emedicine.medscape.com/article/2087713-overview. Accessed 10/15/15.

Evert, A. (2013 February 18, Updated). Chloride in diet. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/002417.htm. Accessed 10/15/15.

Dugdale, D. (2013 May 5, Updated). Chloride test – blood. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003485.htm. Accessed 10/15/15.

Martin, L. (2014 November 2, Updated). Chloride - urine test. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003601.htm. Accessed 10/15/15.

AlAbbad, A. and Sinha, S. (2014 March 13, Updated). Hypochloremic Alkalosis. Medscape Drugs & Diseases [On-line information]. Available online at http://emedicine.medscape.com/article/945263-overview. Accessed 10/15/15.

(Copyright 2004) The National Academies. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. Available online at http://iom.nationalacademies.org/~/media/Files/Activity%20Files/Nutrition/DRIs/DRI_Electrolytes_Water.pdf?la=en. Accessed Oct 2015.

Sources Used in Previous Reviews
Thomas, Clayton L., Editor (1997). Taber's Cyclopedic Medical Dictionary. F.A. Davis Company, Philadelphia, PA [18th Edition].

Pagana, Kathleen D. & Pagana, Timothy J. (2001). Mosby's Diagnostic and Laboratory Test Reference 5th Edition: Mosby, Inc., Saint Louis, MO.

(1995-2004). Minerals and Electrolytes. The Merck Manual of Medical Information – Second Home Edition [On-line information]. Available online at http://www.merck.com/mmhe/sec12/ch155/ch155a.html?qt=electrolytes&alt=sh.

Ben-Joseph, E., Reviewed (2004 July). Dehydration. Familydoctor.org Information for Parents [On-line information]. Available online at http://www.kidshealth.org/PageManager.jsp?dn=familydoctor&lic=44&article_set=21646.

A.D.A.M. editorial, Updated (2003 October 15). Electrolytes. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/002350.htm.

Hurd, R. (Updated April 26, 2007). MedlinePlus Medical Encyclopedia: Serum Chloride. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003485.htm. Accessed July 2008.

Mushnick, R. (Updated October 22, 2007.) MedlinePlus Medical Encyclopedia: Chloride—urine. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003601.htm. Accessed July 2008.

Clarke, W and Dufour D R, Editors (2006). Contemporary Practice in Clinical Chemistry. AACC Press, Washington, DC. Pp 321-322, 326.

Pagana K, Pagana T. Mosby's Manual of Diagnostic and Laboratory Tests. 3rd Edition, St. Louis: Mosby Elsevier; 2006. Pp 165-167.

MedlinePlus Medical Encyclopedia: Chloride in diet. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/002417.htm. Accessed July 2009.

Institute of Medicine. Dietary Reference Intakes: Water, Potassium, Sodium, Chloride, and Sulfate. Available online at http://www.iom.edu/Reports/2004/Dietary-Reference-Intakes-Water-Potassium-Sodium-Chloride-and-Sulfate.aspx. Accessed September 2011.

Pagana and Pagana. Mosby's Manual of Diagnostic and Laboratory Tests. Fourth Edition. Pp 164-166 and 963-964.

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