- 1). Have a radioimmunoassay test of thyroid hormones performed. T3 hormones andT4 hormones are the chief functioning hormones of the thyroid and this test reflects the concentration of these hormones in the blood. If they appear low, your doctor will prescribe medication to increase those levels.
- 2). Have a thyroid binding globulin or TBG test performed. This test evaluates the level of a protein that binds the hormones in the thyroid. Diminished level of this protein could indicate hypothyroidism.
- 3). Have an immunoradiometeric test performed. This test records the production of TSH (thyroid stimulating hormone) from the pituitary gland. A rise in the TSH level shows a drop in the levels of functioning thyroid hormone (normal levels are TSH: 1-5 mlU/L).
- 4). Have an iodine uptake test performed. This test evaluates the absorption capacity of iodine by the cells of thyroid gland. If this test comes back low, it can indicate low thyroid performance.
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