Magnesium Blood Test
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A magnesium blood test measures the amount of magnesium in a sample of your blood. Magnesium is a mineral that helps your muscles, nerves, and heart work properly, controls blood pressure and blood sugar, builds strong bones, and supports your immune system. Your body tightly controls magnesium levels through your kidneys and intestines. Abnormal levels can be caused by many different conditions.
Preparation and collection
There is usually no preparation for a magnesium blood test. If you are having other blood tests at the same time, you may need to fast (not eat or drink) for several hours before your test. Your provider will let you know if you need to prepare. Tell your provider about any prescription and over-the-counter medicines and/or supplements you are taking.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- The amount of magnesium in your blood may be normal even though the amount stored in your body is low. Your provider may order a magnesium in urine test or a magnesium red blood cell (RBC) test for more information.
- name
- Magnesium Blood Test
- nextSteps
- Treatment for abnormal magnesium levels will depend on your condition. Your provider will discuss next steps with you.
What to do next
Treatment for abnormal magnesium levels will depend on your condition. Your provider will discuss next steps with you.