Thyroid hormones help regulate the way the body uses energy. You need
thyroid hormone replacement when you do not have enough thyroid hormones in
your blood (hypothyroidism). Depending on the cause of your
hypothyroidism, you may need to take thyroid hormones for the rest of your
Thyroid hormones are usually taken by mouth. How much you need
depends on your age, your body weight, and whether you are pregnant.
Thyroid hormone replacement is the only way to treat hypothyroidism.
For most people, taking a thyroid hormone medicine:
Reduces or stops the symptoms of
Allows them to live normal
Reduces the risk of complications from having too little
thyroid hormone in the blood, including a high level of fats and cholesterol in
People who take thyroid hormones need to have their blood checked
regularly to make sure that they are taking the correct dose of replacement
hormone. Children, pregnant women, and older adults may need to have their
blood levels checked more often than other people.
For more information about thyroid hormone replacement and
hypothyroidism, see the topic Hypothyroidism.