Unlike Mainstream Medicine, Integrative Medicine believes that you can have a low functioning thyroid (Hypothyroidism), even if your thyroid lab studies are normal. In other words, if you have a Hypothyroid symptoms such as fatigue, weight gain or unable to lose weight, hair loss, low Temperature, constipation, depressed mood and slow heart rate, [and your TSH (Thyroid Stimulating Hormone, made in the Pituitary Gland), FT4 (Free T4, Inactive thyroid made in the Thyroid Gland, and needs to be converted to Free T3) and FT3 (Active thyroid, made peripherally outside the Thyroid Gland) are normal] you can be Hypothyroid and benefit from thyroid replacement. The replacement would be in the form of a prescription that contains Active T3, in combination with Inactive T4. The ideal combination would be in the form of Compounded Bioidentical (Identical to Human Thyroid Hormone) prescription.
The rationale is that FT4 is converted to an Inactive T3 called Reverse T3 (RT3), which is non-functional. Therefore, although the TSH, FT4 and FT3 lab values appear normal when measured, much of the T3 is Inactive making the Thyroid Gland under active and creating Hypothyroid symptoms. Since the Reverse Inactive T3 (RT3) fluctuates up and down in the body, it can be missed when the lab is measured. When the TSH, FT4, FT3 and “even” the RT3 are normal and Hypothyroid symptoms are present, it is necessary to document a week’s worth of average temperatures under 98.6, in order to justify thyroid hormone replacement treatment. The low temperatures imply a low metabolism and a Hypothyroid state.