The bulk of the magnesium in the body is confined to bone cells and thus, very little amount of magnesium circulates in the blood. Magnesium plays a vital role in energy metabolism, maintenance of strong bones, and proper functioning of nerve cells and muscle cells in the body.
Why is the test ordered?
A magnesium test may be ordered to determine the cause of nerve and muscle problems, heart problems, muscle weakness and low potassium and calcium levels that refuse to improve with treatment.
When is the test ordered?
A physician may order the magnesium test suspecting its deficiency if an individual shows the following signs and symptoms:
- Muscle cramping
- Cardiac arrhythmias
The test may also be ordered following potassium and calcium tests if their levels are found to be low. The test is also effective in monitoring the effectiveness of treatment given for low magnesium levels.
How is the sample collected?
A blood sample is collected from a vein in the arm.
How to prepare for the test?
The person taking the test may be asked to fast overnight before taking the test.