Blood Calcium Test: About Your Child's Test

What is it?

A test for calcium in the blood is a blood test to check the level of calcium in your child's body that isn't stored in the bones. Almost all of the calcium in the body is stored in bone. The rest is found in the blood.

The body needs calcium to build and fix bones and teeth, to help nerves work, to make muscles squeeze together, to help blood clot, and to help the heart to work.

Why is this test done?

A blood calcium test may be done:

• To check for problems with the parathyroid glands or kidneys.
• To look for certain types of cancers and bone problems or for inflammation of the pancreas.
• To see if your child has a very low calcium level in the blood.
• To see if your child has a very high calcium level in the blood.

This test can't be used to check for a lack of calcium in your child's diet. It also can't check for a loss of calcium from your child's bones.

How do you prepare for the test?

In general, you don't need to prepare before your child has this test. Your doctor may give you some specific instructions.

How is the test done?

A health professional uses a needle to take a blood sample, usually from the arm.