Proceeds from website advertising help sustain Lab Tests Online. AACC is a not-for-profit organization and does not endorse non-AACC products and services.


Print this article
Share this page:
Also known as: Tg; TGB
Formal name: Thyroglobulin, Serum or Plasma

Board approvedAll content on Lab Tests Online has been reviewed and approved by our Editorial Review Board.

At a Glance

Why Get Tested?

To monitor treatment of thyroid cancer and to detect recurrence; less commonly, to help determine the cause of hyperthyroidism and hypothyroidism

When to Get Tested?

Prior to and after the completion of treatment for thyroid cancer, before and after radioactive iodine therapy, and at regular intervals to monitor for recurrence; it may be ordered in conjunction with other thyroid tests for certain thyroid disorders.

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?

Usually none; however, depending on the laboratory method used for measurement of thyroglobulin, some dietary supplements such as multivitamins or supplements rich in vitamin B7 (Biotin) should not be taken at least 12 hours before the test is performed in order to avoid any test interference that may lead to false results.

Based on information provided by the lab, your healthcare practitioner should inform you if this or any other preparation is necessary.