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Liotrix

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

Medically reviewed by Drugs.com on Apr 9, 2020 – Written by Cerner Multum

What is liotrix?

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

Liotrix is used to treat hypothyroidism (low thyroid hormone).

Liotrix is used in combination with antithyroid medication to treat thyrotoxicosis (excess thyroid hormone).

Liotrix is also used to treat or prevent goiter (enlarged thyroid gland).

Liotrix is also given as part of a medical tests for thyroid disorders.

Liotrix should not be used to treat obesity or weight problems.

Liotrix may also be used for purposes not listed in this medication guide.

Important Information

Liotrix should not be used to treat obesity or weight problems.

You may not be able to use liotrix if you have thyrotoxicosis or an adrenal gland problem that is not controlled by treatment.

Stop taking liotrix and call your doctor if you have symptoms 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 liotrix. However, you may not be able to use this medicine if you have:

  • an adrenal gland problem that is not controlled by treatment;

  • thyrotoxicosis that is not treated with antithyroid medication; or

  • certain heart conditions.

Tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding.

Follow your doctor's instructions about using this medicine if you are pregnant or you become pregnant. Controlling diabetes is very important during pregnancy, and having high blood sugar may cause complications in both the mother and the baby.

How should I take liotrix?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Older adults may be more sensitive to the effects of liotrix, and may need a lower dose than adults younger than 65.

Your thyroid function will need to be tested often. Even if you have no symptoms, tests can help your doctor determine if liotrix is effective.

If you need surgery, tell your surgeon you currently use this medicine. You may need to stop for a short time.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using liotrix.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

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 liotrix?

Follow your doctor's instructions about any restrictions on food or beverages. You may need to avoid certain foods that are high in fiber and can make it harder for your body to absorb liotrix.

Do not change brands or change to a generic 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.

Liotrix side effects

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

Stop using liotrix and call your doctor if you have symptoms of thyroid toxicity, such as chest pain, fast or pounding heartbeats, feeling hot or nervous, or sweating more than usual.

Also call your doctor at once if you have:

  • vomiting, diarrhea;

  • fever, swollen glands, itching, joint pain, or not feeling well;

  • flushing (sudden warmth, redness, or tingly feeling);

  • chest pressure spreading to your jaw or shoulder;

  • shortness of breath;

  • weak or shallow breathing;

  • headache, tremors, trouble sleeping, feeling nervous or irritable;

  • changes in weight or appetite;

  • changes in your menstrual periods;

  • severe headaches, ringing in your ears, dizziness, vision problems, pain behind your eyes;

  • thinking problems, trouble concentrating, poor academic performance; or

  • (in a child or teenager) pain, stiffness, and trouble moving the legs.

Common side effects may include:

  • headache, tiredness, mood changes;

  • tremors, feeling anxious;

  • fast heart rate, increased blood pressure;

  • muscle weakness;

  • increased appetite;

  • stomach cramps;

  • hair loss; or

  • abnormal liver function tests.

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.

Liotrix dosing information

Usual Adult Dose for Hypothyroidism:

Initial dose: Levothyroxine 25 mcg-liothyronine 6.25 mcg orally once a day; increase in increments of 1 tablet of levothyroxine 12.5 mcg-liothyronine 3.1 mcg every 2 to 3 weeks
-A lower initial dose is recommended in patients with long-standing myxedema: Levothyroxine 12.5 mcg-liothyronine 3.1 mcg orally once a day is recommended, particularly if cardiovascular impairment is suspected; extreme caution should be used.
Maintenance dose: Most patients require levothyroxine 50 mcg-liothyronine 12.5 mcg (1 tablet) to levothyroxine 100 mcg-liothyronine 25 mcg (1 tablet) orally per day

Comments:
-Failure to respond to doses of levothyroxine 150 mcg-liothyronine 37.5 mcg (1 tablet) suggests lack of compliance or malabsorption.

Uses: For use as replacement or supplemental therapy in patients with hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis

Usual Pediatric Dose for Hypothyroidism:

0 to 6 months: Levothyroxine 12.5 mcg-liothyronine 3.1 mcg to levothyroxine 25 mcg-liothyronine 6.25 mcg orally per day
6 to 12 months: Levothyroxine 25 mcg-liothyronine 6.25 mcg to levothyroxine 37.5 mcg-liothyronine 9.35 mcg orally per day
1 to 5 years: Levothyroxine 37.5 mcg-liothyronine 9.35 mcg to levothyroxine 50 mcg-liothyronine 12.5 mcg orally per day
6 to 12 years: Levothyroxine 50 mcg-liothyronine 12.5 mcg to levothyroxine 75 mcg-liothyronine 18.75 mcg orally per day
Over 12 years: Doses over levothyroxine 75 mcg-liothyronine 18.75 mcg orally per day

Comments:
-Infants with congenital hypothyroidism should begin therapy with full doses as soon as the diagnosis is made.
-Routine determination of thyroid status, including serum T4 and/or thyroid stimulating hormone (TSH) are recommended in all patients, especially neonates, in view of the deleterious effects of thyroid deficiency on growth and development.

Use: For the treatment of congenital hypothyroidism

What other drugs will affect liotrix?

Some medicines can make liotrix much less effective when taken at the same time. If you take any of the following medicines, take your liotrix dose 4 hours before you take the other medicine.

Tell your doctor about all your current medicines. Many drugs can affect liotrix, especially:

This list is not complete and many other drugs may affect liotrix. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

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.