Clinical Use:
Background: Potassium is a predominantly intracellular cation and only about 2 percent of the amount in the body is in the extracellular fluid. This low extracellular concentration of potassium ions is important for normal neuromuscular activity and cardiac action. Hypokalaemia is usually the result of potassium depletion, although potassium depletion is not always accompanied by hypokalaemia, it can occur, without potassium depletion if there is a shift into the cells. Hyperkalaemia occurs when the rate of potassium leaving cells is greater than its rate of excretion. This occurs in acidosis of any kind but particularly in the presence of a low glomerular filtration rate. Hyperkalaemia can also result from aldosterone deficiency due to Addisons disease and may also be the result of over enthusiastic potassium therapy.Potassium measurements are used to monitor electrolyte balance in the diagnosis and treatment of primary aldosteronism, metabolic alkalosis, diarrhea, severe vomiting, diuretic administration, diabetic ketoacidosis, and other diseases.
Reference Ranges: Serum
Adult: 3.5 – 5.3 mmol/L
Neonate: 3.4 – 6.0 mmol/L
Infant: 3.5 – 5.7 mmol/L
1 to 16 years: 3.5 – 5.0 mmol/L
25 – 125 mmol/24hrs
Associated Diseases:
Patient Preparation:
Specimen Requirements: Sample type:

  • Serum, Lithium Heparin Plasma or Plain Urine (random or 24 hour).

Sample identification:

  • Three patient identifiers from
    • Name
    • D.O.B.
    • Address
    • N.H.S. number
    • Unit Number

    should match on the specimen and request form. This check may be performed prior to centrifugation by the Central Sort department.

Turnaround Time: 2 hours
Additional Information:
Referred Test: