Blood tests do not check the thyroid gland. Thyroid blood tests usually check for thyroid hormones. Thyroid hormones mainly include T3 (total triiodothyronine), T4 (total thyroxine), FT3 (free triiodothyronine), FT4 (free thyroxine), and TSH (thyroid stimulating hormone), which are commonly known as the five thyroid hormones. If the results are within the normal range of the reference values, the results are normal. If the results suggest that FT3, FT4, T3, T4 is elevated and TSH is lowered, hyperthyroidism is considered, and if FT3, FT4, T3, T4 is lowered and TSH is elevated, hypothyroidism is considered. It is recommended to follow the doctor’s instructions to check the thyroid gland.