Calcitonin is a test that measures the amount of the hormone calcitonin in the blood.
A blood sample is needed. For information on how this is done, see: Venipuncture
There is usually no special preparation needed.
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
The health care provider may suggest a calcitonin test when you have symptoms of medullary thyroid cancer or MEN syndrome, or a family history of these conditions. Calcitonin may also be higher in other tumors, such as:
Calcitonin is a hormone produced in the C cells of the thyroid gland. Its role in humans is unclear. In animals, calcitonin helps to regulate blood calcium by slowing down the amount of calcium released from the bones. Calcitonin works in the opposite way as parathyroid hormone (PTH) and 1,25-dihydroxy vitamin D.
A normal value is less than 10 picograms per milliliter (pg/mL).
Males and females can have different normal values. Sometimes, health care providers take a second or even a third calcitonin blood level after an intravenous (IV) infusion of calcium, especially when the health care worker suspects medullary carcinoma of the thyroid. You will need this extra test if your baseline calcitonin is normal.
The examples above are common measurements for results for these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your specific test results.
Higher-than-normal levels may indicate:
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include: