Thyroid function tests are used to tell whether your thyroid is working normally.
The most common thyroid function tests are:
- Total, or free T4 (the main thyroid hormone in your blood)
- TSH (the hormone from the pituitary gland that stimulates the thyroid to produce T4)
- T3 (also included sometimes)
Other thyroid tests include:
Guber HA, Farag AF. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds.Henry's Clinical Diagnosis and Management by Laboratory Methods
Salvatore D, Davies TF, Schlumberger MJ, et al. Thyroid physiology and diagnostic evaluation of patients with thyroid disorders. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, Larsen PR, et al, eds.Williams Textbook of Endocrinology
Update Date 5/10/2014
Updated by: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.