1.Basal Body Temperature: The temperature is taken when the body is at complete rest, immediately after waking and before beginning any activity. The normal basal temperature is 36.4 – 36.7 ºC, and some alternative practitioners believe that a 5-day consecutive temperature reading below 36.4 ºC is indicative of hypothyroidism. However, a thyroid panel blood test should be taken to accurately evaluate the thyroid function.
2.Tests for T4 and T3: Thyroid hormones can be tested in both their free and protein-bound forms. Tests for the protein-bound forms and unbound form of T4 or T3 are generally referred to as Total T4 or Total T3 respectively; unbound forms are called Free T4 and Free T3. Each of these tests gives information about how the body is making, activating, and responding to thyroid hormone. Levels of free T3 and T4 will be below normal in clinical hypothyroidism. In subclinical hypothyroidism the TSH will be elevated while the thyroid hormone levels are still in the normal reference range.
3.Reverse T3: Certain individuals with apparently normal T4 and T3 hormone levels still display the classic symptoms of hypothyroidism. This may be due to an excessive production of reverseT3 (rT3). rT3 is inactive and may interfere with the action of T3 in the body. Stress and extreme exercise may play a role in lowering thyroid hormone action by suppressing production of TSH and T3 and elevating rT3 levels.
4.Autoimmune antibodies: When evaluating the thyroid it is also important to consider that the most common cause of overt hypothyroidism is an autoimmune disorder known as Hashimoto’s thyroiditis. This condition causes the body to produce antibodies to the thyroid gland and damage the gland. Hashimoto’s thyroiditis is diagnosed by standard thyroid testing in conjunction with testing for the presence of these antibodies called antithyroglobulin antibodies (AgAb) and thyroperoxidase antibodies (TPOAb). Some people with celiac disease or sensitivity to gluten are at increased risk for developing autoimmune thyroid disease and should be evaluated.
5.Elevated thyroid antibodies are often associated with chronic urticaria, also called hives. Studies report that as many as 57.4% of patients with hives have the presence of anti-thyroid antibodies. A 2010 study suggests that treatment with T4 improves the itching associated with urticaria, but did not advise treatment with T4 unless the patient was hypothyroid.
6.Additional testing: Sometimes biopsy or enzymatic studies are required to establish a definite diagnosis for thyroid dysfunction. Major abnormalities of the thyroid gland detected in physical exam can be further assessed by ultrasound or a procedure known as scintigraphy.
7.Hypothalamic pituitary axis (HPA): There is an intimate relationship between the thyroid, the adrenal glands and the sex hormones. If hypothyroidism is suspected, an evaluation of the adrenal glands as well as the sex hormones is suggested. Your doctor will perform a clinical examination and request some blood tests.