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Thyrolar-1/2

Generic Name: liotrix (LYE oh trix)
Brand Name: Thyrolar-1, Thyrolar-1/2, Thyrolar-1/4, Thyrolar-2, Thyrolar-3

Medically reviewed on December 15, 2017

What is Thyrolar-1/2?

Thyrolar-1/2 is a man-made form of a hormone that is normally produced by your thyroid gland to regulate the body's energy and metabolism. This medicine is given when the thyroid does not produce enough of this hormone on its own.

Thyrolar-1/2 treats hypothyroidism (low thyroid hormone). This medicine is also used to treat or prevent goiter (enlarged thyroid gland), and is also given as part of a medical tests for thyroid disorders.

Thyrolar-1/2 should not be used to treat obesity or weight problems.

Thyrolar-1/2 may also be used for purposes not listed in this medication guide.

Important Information

Since thyroid hormone occurs naturally in the body, almost anyone can take Thyrolar-1/2. However, you may not be able to use this medication if you have a thyroid disorder called thyrotoxicosis, or an adrenal gland problem that is not controlled by treatment.

Before taking Thyrolar-1/2, tell your doctor if you have heart disease, angina (chest pain), coronary artery disease, congestive heart failure, diabetes, or problems with your pituitary or adrenal glands.

Tell your doctor if you are pregnant or breast-feeding.

To be sure this medication is helping your condition, your blood may need to be tested often. Visit your doctor regularly.

Keep using Thyrolar-1/2 as directed, even if you feel well. You may need to take thyroid medication for the rest of your life.

Call your doctor if you notice any signs of thyroid toxicity, such as chest pain, fast or pounding heartbeats, feeling hot or nervous, or sweating more than usual.

Before taking this medicine

Since thyroid hormone occurs naturally in the body, almost anyone can take Thyrolar-1/2. However, you may not be able to use this medication if you have a thyroid disorder called thyrotoxicosis, or an adrenal gland problem that is not controlled by treatment.

To make sure you can safely take Thyrolar-1/2, tell your doctor if you have any of these other conditions:

  • heart disease, angina (chest pain);

  • coronary artery disease;

  • congestive heart failure;

  • any type of diabetes; or

  • problems with your pituitary or adrenal gland.

FDA pregnancy category A. Thyrolar-1/2 is not expected to harm an unborn baby. However, tell your doctor if you become pregnant, since your dose needs may be different during pregnancy.

Small amounts of liotrix can pass into breast milk, but this is not expected to harm a nursing baby. However, do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take Thyrolar-1/2?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Your doctor may occasionally change your dose to make sure you get the best results.

To be sure this medication is helping your condition, your blood may need to be tested often. Visit your doctor regularly.

Keep using Thyrolar-1/2 as directed, even if you feel well. You may need to take thyroid medication for the rest of your life.

Call your doctor if you notice any signs of thyroid toxicity, such as chest pain, fast or pounding heartbeats, feeling hot or nervous, or sweating more than usual.

If you need surgery, tell the surgeon ahead of time that you are using Thyrolar-1/2. You may need to stop using the medicine for a short time.

Store Thyrolar-1/2 tablets in a tightly closed container in the refrigerator. Protect the medicine from light and do not allow it to freeze.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include headache, sweating, diarrhea, irregular menstrual periods, confusion, weakness, swelling in your hands or feet, fast heart rate, chest pain, feeling short of breath, fainting, or feeling nervous, restless, or irritable.

What should I avoid while taking Thyrolar-1/2?

Do not change brands or change to a generic drug product without first asking your doctor. Different brands of liotrix may not work the same. If you get a prescription refill and your new pills look different, talk with your pharmacist or doctor.

If you also take cholestyramine (Prevalite, Questran) or colestipol (Colestid), avoid taking these medications within 4 hours before or after you take Thyrolar-1/2.

Thyrolar-1/2 side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Thyrolar-1/2?

Tell your doctor about all other medicines you use, especially:

This list is not complete and other drugs may interact with Thyrolar-1/2. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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