Thyroxine (T4) is the most common form of thyroid hormone that is
released by the thyroid gland. Once it reaches the tissues, it is converted to
another form of thyroid hormone called triiodothyronine (T3), which is more
active in regulating the body's chemical reactions.
In tests of thyroid function, a low T4 level may indicate the
presence of low thyroid levels (hypothyroidism). Certain forms of liver or
kidney disease may also cause a low T4 level, even though a thyroid problem may
not be present.
E. Gregory Thompson, MD - Internal Medicine & Matthew I. Kim, MD - Endocrinology
PeaceHealth endeavors to provide comprehensive health care information, however some topics in this database describe services and procedures not offered by our providers or within our facilities because they do not comply with, nor are they condoned by, the ethics policies of our organization.