Examples
| levothyroxine (T4) |
Levothroid, Levoxyl, Synthroid, Tirosint, Unithroid |
| liothyronine (T3) |
Cytomel |
| liotrix (T3 and T4) |
Thyrolar |
Thyroid hormones are taken by mouth (orally) except in
unusual cases, such as
myxedema coma. That condition requires
intravenous (IV) medicine. Dosages vary with the
person's age and the severity of the disease.
How It Works
People with
hypothyroidism have lower-than-normal or no thyroid
function and do not make enough thyroid hormone for the body to function
properly. Taking thyroid hormone medicine replaces missing hormones.
Why It Is Used
Thyroid hormone medicines are given
when blood tests show that you have hypothyroidism.
Thyroid hormone
medicines also may be prescribed:
How Well It Works
People with hypothyroidism who take
thyroid hormone medicine usually notice:
- Improved energy level.
- Gradual
weight loss (in people with severe hypothyroidism at the time of
diagnosis).
- Improved mood and mental function (thinking,
memory).
- Improved pumping action of the heart and improved
digestive tract function.
- Reduction in the size of an enlarged
thyroid gland (goiter), if you have one.
- Improved growth, school
performance, and behavior in children. Children whose growth has been delayed
because of hypothyroidism start growing normally again when they are getting adequate
doses of thyroid hormone.
- Lower
cholesterol and
triglyceride levels.
In most cases, thyroid hormone medicine works quickly to
correct symptoms.
Myxedema coma can respond well to thyroid
hormone medicine and treatment in an intensive care unit. But a good outcome
depends on how soon treatment starts.
Side Effects
All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.
Here are some important things to think about:
- Usually the benefits of the medicine are more important than any minor side effects.
- Side effects may go away after you take the medicine for a while.
- If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.
Call
911
or other emergency services right away if you have:
- Trouble breathing.
- Swelling of your face, lips, tongue, or throat.
- Chest pain.
Call your doctor if you have:
- Hives.
-
Heart palpitations
.
- Nervousness.
- Trouble sleeping
(insomnia).
- Shaking (tremors).
- Frequent bowel
movements or diarrhea.
- Too much weight loss.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Certain medicines can
affect the way thyroid medicines work. People taking the following medicines
need to see their doctor often to make sure they are getting the correct dose
of thyroid hormone medicine. Some of these medicines include:
- Calcium. Take calcium supplements at least 4 hours before or after taking thyroid hormone
medicine.
- Iron supplements.
- Birth control pills or other hormones.
- Cholestyramine.
- Sucralfate and some antacids containing aluminum hydroxide.
- Some seizure medicines.
- Some antibiotics used to treat tuberculosis.
Taking medicine
Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.
There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.
Advice for women
If you are pregnant, breast-feeding, or planning to get pregnant, do not use any medicines unless your doctor tells you to. Some medicines can harm your baby. This includes prescription and over-the-counter medicines, vitamins, herbs, and supplements. And make sure that all your doctors know that you are pregnant, breast-feeding, or planning to get pregnant.
Checkups
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.
Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.
Credits
|
By
|
Healthwise Staff |
|
Primary Medical Reviewer
|
Kathleen Romito, MD - Family Medicine |
|
Specialist Medical Reviewer
|
Matthew I. Kim, MD - Endocrinology |
|
Last Revised
|
August 7, 2012 |