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Drugs & Medications

liothyronine

COMMON BRAND NAME(S): Cytomel

GENERIC NAME(S): LIOTHYRONINE SODIUM

WARNINGS:

This medication should not be used either alone or in combination with diet pills to treat obesity/cause weight loss in patients with normal thyroid production. If used in combination with diet pills (appetite suppressant drugs), serious, even life-threatening effects could occur.

Who should not take liothyronine?
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Uses

Liothyronine is used to treat underactive thyroid (hypothyroidism). It replaces a hormone that is normally produced by the thyroid gland. Low thyroid levels can occur naturally or when the thyroid gland is injured by radiation/medications or removed by surgery. It is important to have adequate levels of thyroid hormone in your bloodstream to maintain normal mental and physical activity.

This medication is also used to lower thyroid function in certain diseases such as enlarged thyroid gland (goiter) and Hashimoto's thyroiditis. It is also used to test thyroid activity. Liothyronine is a man-made hormone that replaces the body's natural thyroid hormone (T3).

OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used to treat thyroid cancer.

Liothyronine should not be used for treating infertility in patients with normal thyroid levels. The risks of use are high, and liothyronine provides no benefit.

How to use liothyronine

Take this medication by mouth with or without food, usually once daily in the morning or as directed by your doctor.

Dosage is based on your medical condition, thyroid levels and response to therapy.

Take this medication 4 hours before or after taking any products containing aluminum or iron, such as antacids, sucralfate, and vitamins/minerals. Take liothyronine 4 hours before or after taking cholestyramine or colestipol. These products react with liothyronine, preventing its full absorption.

Use this medication regularly in order to get the most benefit from it. To help you remember, use it at the same time each day. Do not stop taking this medication without talking with your doctor. Thyroid replacement therapy is usually taken for life.

Symptoms of low thyroid levels include tiredness, muscle aches, constipation, dry skin, weight gain, slow heart rate, and sensitivity to cold. These symptoms should lessen as your body adjusts to the medication. It may take several days before you see an improvement in your condition. Inform your doctor if your condition does not improve or if it worsens after 2 to 3 days of treatment.

Side Effects

Nausea may occur. In rare instances, some temporary hair loss may occur during the first few months of starting this drug (especially in children). If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Though unlikely, it is possible to have too much thyroid hormone. Tell your doctor immediately if any of these unlikely but serious signs of too much thyroid hormone occur: headache, irritability, trouble sleeping, nervousness, increased sweating, heat intolerance, diarrhea, menstrual changes.

Seek immediate medical attention if any of these rare but very serious side effects occur: chest pain, trouble breathing with exercise, fast/irregular/pounding heartbeat, swelling of the arms/legs, extreme weakness.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking liothyronine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: decreased adrenal gland function, kidney disease (e.g., nephrosis), low pituitary hormone (e.g., hypopituitarism), low testosterone (e.g., hypogonadism), overactive thyroid (hyperthyroidism).

Before using this medication, tell your doctor or pharmacist your medical history, especially of: heart disease (e.g., angina, high blood pressure, heart failure, irregular heartbeat, heart attack), sugar diabetes (diabetes mellitus), water diabetes (diabetes insipidus), long-term severe underactive thyroid (e.g., myxedema).

Before having surgery, tell your doctor or dentist that you are using this medication.

If you have diabetes, this drug may make it harder to control your blood sugar levels. Check your blood sugar regularly as directed by your doctor. Tell your doctor immediately if you have symptoms such as increased thirst/urination, shakiness, unusual sweating, or hunger. Your anti-diabetic medication or diet may need to be adjusted.

Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be at a greater risk for heart problems while using this drug.

Children may be more sensitive to the effects of thyroid hormones.

Current information shows that this drug may be used during pregnancy. Consult your doctor before becoming pregnant.

Liothyronine passes into breast milk. While there have been no reports of harm to nursing infants, consult your doctor before breast-feeding.

Interactions

See also How to Use section.

Your healthcare professionals (e.g., doctor or pharmacist) may already be aware of any possible drug interactions and may be monitoring you for it. Do not start, stop or change the dosage of any medicine before checking with them first.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: certain antidepressants (e.g., TCAs such as amitriptyline, imipramine, nortriptyline), estrogen (e.g., hormone replacement therapy, birth control pill/patch/ring), digoxin, ketamine, intravenous blood pressure drugs (e.g., epinephrine, norepinephrine), "blood thinners" (e.g., warfarin).

Check the labels on all your medicines (e.g., cough-and-cold products, diet aids) because they may contain ingredients such as decongestants that could increase your heart rate or blood pressure. Ask your pharmacist about the safe use of those products.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: fever, fast/irregular heartbeat, chest pain, confusion.

Notes

Do not share this medication with others.

Laboratory and/or medical tests (e.g., thyroid function tests) should be performed regularly to monitor your progress or check for side effects. Some drugs (e.g., androgens, corticosteroids, estrogens, estrogen-containing birth control pills, iodine-containing products, salicylates) can interfere with thyroid function tests, possibly causing false test results. Consult your laboratory personnel or doctor for more details.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up unless your doctor instructs you to do so. Call your doctor if you miss 2 or more doses in a row. Ask your doctor ahead of time what to do about a missed dose and follow your doctor's specific directions.

Storage

Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.

Images

CYTOMEL 5 MCG TABLET
CYTOMEL 5 MCG TABLET
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LIOTHYRONINE SOD 5 MCG TAB
LIOTHYRONINE SOD 5 MCG TAB
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CYTOMEL 25 MCG TABLET
CYTOMEL 25 MCG TABLET
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LIOTHYRONINE SOD 25 MCG TAB
LIOTHYRONINE SOD 25 MCG TAB
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CYTOMEL 50 MCG TABLET
CYTOMEL 50 MCG TABLET
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LIOTHYRONINE SOD 50 MCG TAB
LIOTHYRONINE SOD 50 MCG TAB
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M L, 13
CYTOMEL 5 MCG TABLET
CYTOMEL 5 MCG TABLET

Identification

color
No data.
shape
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imprint
No data.
This medicine is a white, round tablet imprinted with "KPI" and "115".
LIOTHYRONINE SOD 5 MCG TAB
LIOTHYRONINE SOD 5 MCG TAB

Identification

color
white
shape
round
imprint
ML, 11
This medicine is a white, round tablet imprinted with "ML" and "11".
CYTOMEL 25 MCG TABLET
CYTOMEL 25 MCG TABLET

Identification

color
No data.
shape
No data.
imprint
No data.
This medicine is a white, round, scored tablet imprinted with "JMI D16".
LIOTHYRONINE SOD 25 MCG TAB
LIOTHYRONINE SOD 25 MCG TAB

Identification

color
white
shape
oval
imprint
M L, 12
This medicine is a white, oval, scored tablet imprinted with "M L" and "12".
CYTOMEL 50 MCG TABLET
CYTOMEL 50 MCG TABLET

Identification

color
No data.
shape
No data.
imprint
No data.
This medicine is a white, round tablet imprinted with "KPI" and "117".
LIOTHYRONINE SOD 50 MCG TAB
LIOTHYRONINE SOD 50 MCG TAB

Identification

color
white
shape
oblong
imprint
M L, 13
This medicine is a white, oblong, scored tablet imprinted with "M L" and "13".

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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