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Also known as: Mg; Mag
Formal name: Magnesium

At a Glance

Why Get Tested?

To evaluate the level of magnesium in your blood and to help determine the cause of abnormal levels of magnesium, calcium and/or potassium

When to Get Tested?

When you have symptoms such as weakness, irritability, cardiac arrhythmia, nausea, and/or diarrhea that may be due to too much or too little magnesium; when you have abnormal calcium or potassium levels

Sample Required?

A blood sample drawn from a vein in your arm; sometimes a timed urine collection that most often requires a 24-hour sample

Test Preparation Needed?

For a blood sample, overnight fasting may be required; follow any instructions that you are given.