Magnesium blood tests may be used to evaluate kidney problems or uncontrolled diabetes or gastrointestinal concerns. Magnesium blood testing may also be useful in assisting in the diagnosis for problems with calcium, potassium, or phosphorus. Patients testing for magnesium deficiency should note that the Magnesium RBC test may provide an earlier indication of lowered magnesium levels. Turnaround time for Magnesium blood tests is typically 1-3 business days.
The Magnesium blood test has no fasting requirements.