Liothyronine: MedlinePlus Drug Information

T IMPORTANT WARNING:
P Thyroid hormone should not be used to treat obesity in patients with normal thyroid function. Liothyronine is ineffective for weight reduction in normal thyroid patients and may cause serious or life-threatening toxicity, especially when taken with amphetamines. Talk to your doctor about the potential risks associated with this medication.

T Why is this medication prescribed?
P Liothyronine is used to treat hypothyroidism (a condition where the thyroid gland does not produce enough thyroid hormone). Liothyronine is also used to treat a goiter (an enlarged thyroid gland) and to test for hyperthyroidism (a condition where the thyroid gland produces too much thyroid hormone). Liothyronine is in a class of medications called thyroid agents. It works by supplying the thyroid hormones normally produced by the body.
P Currently, there is not enough evidence from clinical studies to support the use of liothyronine, alone or in combination with other medications, as the first choice of therapy to treat hypothyroidism.

T How should this medicine be used?
P Liothyronine comes as a tablet to take by mouth. It usually is taken once daily. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take liothyronine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
P Your doctor will probably start you on a low dose of liothyronine and gradually increase your dose not more than once every 1 to 2 weeks.
P To control the symptoms of hypothyroidism, you probably will need to take this medication for the rest of your life. Continue to take liothyronine even if you feel well. Do not stop taking liothyronine without talking to your doctor.

T Other uses for this medicine
P This medication may be prescribed for other conditions; ask your doctor or pharmacist for more information.

T What special precautions should I follow?
t Before taking liothyronine,
- tell your doctor and pharmacist if you are allergic to liothyronine, thyroid hormone, levothyroxine, any other medications, or any of the ingredients in liothyronine tablets. Ask your pharmacist for a list of the ingredients.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven); diabetes medications taken by mouth; digoxin (Lanoxin); estrogens; insulin;oral contraceptives containing estrogen; and tricyclic antidepressants such as amitriptyline (Elavil). Many other medications may also interact with liothyronine, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
- if you take cholestyramine (Questran),take it at least 4 to 5 hours before or 4 to 5 hours after you take liothyronine.
- tell your doctor if you have adrenal insufficiency (condition in which the body does not produce enough of certain natural substances needed for important functions such as blood pressure) or thyrotoxicosis (condition that occurs from too much thyroid hormone or hyperthyroidism). Your doctor will probably tell you not to take liothyronine.
- tell your doctor if you have or have ever had diabetes; cardiovascular disease such as high blood pressure, atherosclerosis (hardening of the arteries), chest pain (angina), or irregular heartbeat, or have ever had a heart attack.
- tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking liothyronine, call your doctor.
- if you have surgery, including dental surgery, tell the doctor or dentist that you are taking liothyronine.

T What special dietary instructions should I follow?
P Unless your doctor tells you otherwise, continue your normal diet.

T What should I do if I forget a dose?
P Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

T What side effects can this medication cause?
t Liothyronine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- weight loss
- nervousness
- excessive sweating
- sensitivity to heat
- temporary hair loss (particularly in children during the first months of therapy)
t Some side effects can be serious. If you experience either of the following symptoms, call your doctor immediately:
- chest pain
- rapid or irregular heartbeat or pulse
P If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

T What should I know about storage and disposal of this medication?
P Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
P It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org
P Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

T In case of emergency/overdose
P In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
t Symptoms of overdose may include the following:
- headache
- irritability
- nervousness
- sweating
- increased bowel motility
- menstrual irregularities

T What other information should I know?
P Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to liothyronine.
P Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking liothyronine.
P Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
P It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

T Brand names
- Cytomel®

T Other names
- L-Triiodothyronine

