Magnesium Test

What is the magnesium test?

The magnesium test measures the amount of magnesium in your blood.

Why is this test done?

Magnesium is a very important nutrient for your body. For example, your nerves, digestive system, and heart all need it to work properly. You can get magnesium from foods and supplements.

The magnesium level in your blood may be measured to check your:

• diet
• overall health
• kidney function
• glands and how well they are working

How do I prepare for this test?

• You may need to avoid taking certain medicines before the test because they might affect the test result. Make sure your healthcare provider knows about any medicines, herbs, or supplements that you are taking. Don't stop any of your regular medicines without first consulting with your healthcare provider.
• Talk to your healthcare provider if you have any questions about the test.

How is the test done?

Having this test will take just a few minutes. A small amount of blood is taken from a vein in your arm with a needle. The blood is collected in tubes and sent to a lab.

How will I get the test result?

Ask your healthcare provider when and how you will get the result of your test.

What does the test result mean?

Your blood level of magnesium may be higher than normal if:

• You have kidney disease.
• You have a gland problem; for example, your thyroid gland isn't making enough thyroid hormone.

Your blood level of magnesium may be lower than normal if:

• You aren't getting the nutrients you need from your diet.
• You have frequent or long-lasting diarrhea.
• You drink too much alcohol.
• You have liver, pancreas, or kidney disease.
• You have too much calcium in your blood.
• You have severe burns.
• You have severe infections.
• You are taking certain medicines, such as digoxin, insulin, and diuretics.

What if my test result is not normal?

Test results are only one part of a larger picture that takes into account your medical history and current health. Sometimes a test needs to be repeated to check the first result. Talk to your healthcare provider about your result and ask questions such as:

• if you need more tests
• what kind of treatment you might need
• when you need to be tested again
• what lifestyle, diet, or other changes you might need to make

If your magnesium level is low, your provider may recommend supplements to bring it back up.