What Is a TSH Lab?

Laboratory tests help physicians diagnose and treat diseases and conditions. The TSH lab test helps diagnose and treat hyperthyroidism and hypothyroidism, conditions of the thyroid gland. The test is a blood test and is performed by most laboratories.

Thyroid Gland

• The thyroid gland sits in front of the trachea, just below the Adam's apple. It aids in the regulation of metabolism. Its function is largely dependent on another gland, the anterior pituitary gland.

Anterior Pituitary and TSH

• The pituitary gland is also known as the "master gland" because it regulates the function of other glands. It produces TSH, or thyroid-stimulating hormone, which tells the thyroid when to release thyroxin and how much of it to release.

Thyroid Disease

• People with thyroid disease may experience fatigue, body aches and depression if the thyroid shuts down. They may experience excessive energy, insomnia, and manic episodes if the thyroid is overstimulated.

TSH Test

• Physicians will ask for a TSH test to measure the level of stimulus the pituitary is placing on the thyroid gland. Medication is then given to adjust that stimulus and relieve the symptoms of thyroid disease.

Complexity of the Test

• The TSH lab test is easy for the patient and simple for the lab. The patient does not need any special preparation before providing a blood sample. Most clinical laboratories in the United States are capable of performing this test.