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Serum Calcium

What is it?

Serum calcium is a laboratory test to measure the amount of calcium in your blood. Calcium is absorbed into the bloodstream from the food you eat. The bones and teeth are the storerooms for calcium. Calcium is also needed to help many other systems (parts) in your body work well.

Why do I need it?

Blood levels of calcium are often done to check your health. Whether calcium levels are above or below normal can help explain several conditions. Some of the conditions may include:

  • Cardiac (heart) function.
  • Hormones.
  • Irregular heartbeat.
  • Kidneys.
  • Malignancy (growth).
  • Malnutrition (not eating enough food).
  • Muscle contractions.
  • Nerve transmissions.
For more information, ask your caregiver to explain the test to you and why you need it.

How do I get ready for the test?

Your caregiver will tell you when to have your blood test done. Do not eat or drink anything, except water, for at least 12 hours before the test. Your caregiver will tell you if you should wait to take your medicines until after your blood is taken.

How is the specimen collected?

A caregiver will put a wide rubber strap around your arm and tighten it. Your skin will be cleaned with alcohol. A small needle attached to a special test tube will be put into a vein in your arm or hand. The tube has suction to pull the blood into it. When the tube is full, the rubber strap, needle and tube are removed. The caregiver will press a piece of cotton where the needle was removed. You may be asked to hold the cotton on the site for a few minutes to help stop bleeding. Tape may then be put over the cotton on your arm.

What do I do after the test?

You may remove the tape and cotton in about 20 to 30 minutes. Call your caregiver to get the results of your test. Your caregiver will explain what your test results mean for you. Follow the instructions of your caregiver.

Care Agreement

You have the right to help plan your care. To help with this plan, you must learn about your lab tests. You can then discuss the results with your caregivers. Work with them to decide what care may be used to treat you. You always have the right to refuse treatment.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.