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Cytomel

(liothyronine)

In this factsheet:
• How does Cytomel work? What will it do for me?
• How should I use Cytomel?
• What form(s) does Cytomel come in?
• Who should NOT take Cytomel?
• What side effects are possible with Cytomel?
• Are there any other precautions or warnings for Cytomel?
• What other drugs could interact with Cytomel?

DIN (Drug Identification Number)

How does Cytomel work? What will it do for me?

Thyroid replacement therapy such as liothyronine is used when the thyroid gland does not secrete enough thyroid hormone (hypothyroidism). Thyroid hormone is necessary for increasing the metabolic rate of body tissues. Liothyronine works quickly to restore the normal function of tissues and organs and must be taken on a daily basis to be effective. Replacement thyroid hormone therapy usually needs to be taken for life.

Liothyronine is used to treat hypothyroidism (low blood levels of thyroid hormone), goiter (swelling in the thyroid gland), and myxedema (the body's changes associated with prolonged low blood levels of thyroid hormone).

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

How should I use Cytomel?

The starting adult dose of liothyronine to treat hypothyroidism is 25 µg daily. Based on the results of laboratory tests to determine the amount of thyroid hormone in your blood, your doctor will increase your dose of liothyronine gradually, every 1 to 2 weeks until an appropriate level of thyroid hormone is available in the bloodstream. Do not change the way you take this medication without consulting your doctor.

The starting dose of liothyronine for children when treating hypothyroidism is 5 µg daily, which will be increased every 3 to 4 days until an appropriate response occurs.

The starting adult dose of liothyronine to treat goiter or myxedema is 5 µg daily. Again, based on blood tests, your doctor will gradually increase your dose of liothyronine every 1 to 2 weeks until an appropriate response occurs.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones given here, do not change the way that you are taking the medication without consulting your doctor.

This medication is to be taken once daily, usually before breakfast. Replacement thyroid hormone therapy usually needs to be taken for life.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature. Keep out of reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

What form(s) does Cytomel come in?

5 µg
Each round, mostly white tablet, embossed with "KPI" on one side and embossed with "115" on the other side, contains liothyronine sodium equivalent to liothyronine 5 µg. Nonmedicinal ingredients: calcium sulfate, gelatin, starch, stearic acid, sucrose, and talc.

25 µg
Each round, mostly white tablet, embossed with "KPI" over "116" and the other side of the tablet scored, contains liothyronine sodium equivalent to liothyronine 25 µg. Nonmedicinal ingredients: calcium sulfate, gelatin, starch, stearic acid, sucrose, and talc.

Who should NOT take Cytomel?

Liothyronine should not be taken by anyone who:

• is allergic to liothyronine or to any of the ingredients of the medication
• has certain uncorrected problems of the adrenal glands
• has untreated thyrotoxicosis (too much thyroid hormone in the blood)

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