Blood and lab tests
What Does Chloride Mean on a Blood Test?
Chloride · say it: KLOR-ideAlso written: Cl, Cl-, serum chloride
Short answer
Chloride is an electrolyte that works with sodium to balance body fluids and helps keep your blood's acid level steady.
What it means
Chloride is a mineral that carries a negative electrical charge when dissolved in body fluids. Most of it comes from salt (sodium chloride) in food. Chloride works closely with sodium and water to control how much fluid is in and around your cells, and it plays a part in the acid balance of the blood and in making stomach acid.
Chloride appears on electrolyte panels and on basic and comprehensive metabolic panels. It usually rises and falls with sodium, so doctors look at the two together. When chloride moves differently from sodium, it can be a clue about acid-base balance, and it is used to work out the anion gap. Changes often relate to fluid balance, vomiting, diarrhea, kidney function or intravenous fluids given in hospital.
Chloride in blood is different from chlorine, the chemical used in swimming pools, and from the chloride measured in a sweat test, which is used to check for cystic fibrosis.
Where you may see it
- Electrolyte panels, between sodium and bicarbonate
- Basic and comprehensive metabolic panels
- Hospital blood results checked during IV fluid treatment
📄 How it looks on a report
Chloride 110 mmol/L H
🙅 What it does not mean
- A high chloride is not caused by swimming pools or treated tap water. It reflects the body's salt and fluid balance.
- A small chloride flag on its own is not a diagnosis. Doctors read it alongside sodium, bicarbonate and the anion gap.
- This blood chloride test is not the sweat chloride test. They are done in different ways and answer different questions.
🗒️ Questions to ask your doctor
🧾 Reports where you will see “Chloride”
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💊 Medicines whose labels mention “Chloride”
Plain-English explanations of each medicine, from its official FDA label.
- Chlorthalidone
a thiazide-like diuretic (a water pill)
- Furosemide
A loop diuretic, a type of medicine that helps the body get rid of extra fluid through urine
- Hydrochlorothiazide
A thiazide diuretic, a type of medicine often called a 'water pill'
- Triamterene and Hydrochlorothiazide
a combination water pill (diuretic) that pairs a thiazide diuretic with a potassium-sparing diuretic
🔗 Read more from trusted sources
- “Chloride” on MedlinePlus ↗
US National Library of Medicine
- MedlinePlus lab test guides ↗
US National Library of Medicine
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More words: blood and lab tests
General information about a medical word, not advice about your own results. Ask the clinician who ordered the test what it means for you.