What Is a Blood Test?

By taking and testing a small sample of a person’s blood, doctors can check for many kinds of diseases and conditions. Blood tests help doctors check how the body’s organs are working and see if medical treatments are helpful.

To help your child get ready for a blood test, find out if they need to fast (not eat or drink) or should stop taking medicines before the test. Explain what to expect during the test. If your child is anxious about it, work together on ways to stay calm.

What Is Magnesium?

Magnesium (mag-NEEZ-ee-im) is a mineral that helps muscles, nerves, the immune system, and the heart work as they should. It also helps make protein and energy, and helps keep bones strong.

Why Are Magnesium Tests Done?

This test measures the amount of magnesium in the blood. Doctors may order a magnesium test if a child has signs of low magnesium levels, such as weakness, muscle cramps or twitching, or an unusual heartbeat. The test also can be done if a child has a medical condition that makes abnormal  magnesium levels more likely, such as a kidney problem.

What if I Have Questions?

If you have questions about the magnesium blood test or what the test results mean, talk to your doctor.