Definition of Cl (chloride)

Cl (chloride): Cl is the chemical symbol for chloride, the major anion found in the fluid outside of cells and in blood. An anion is the negatively charged part of certain substances such as table salt (sodium chloride or NaCl) when dissolved in liquid.

The balance of chloride ion (Cl-) is closely regulated by the body. Significant increases or decreases in chloride can have deleterious or even fatal consequences:

  • Increased chloride (hyperchloremia): Elevations in chloride may be seen in diarrhea, certain kidney diseases, and sometimes in over activity of the parathyroid glands.
  • Decreased chloride (hypochloremia): Chloride is normally lost in the urine, sweat, and stomach secretions. Excessive loss can occur from heavy sweating, vomiting, adrenal gland disease, or kidney disease.

The normal serum range for chloride is 98 - 108 mmol/L.


Last Editorial Review: 9/20/2012

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