Triostat

Triostat is used as treatment for a complication of severe hypothyroidism called myxedema coma.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• antidepressants
• vasopressors
• cholestyramine (Prevalite, Questran)
• colesevelam (Welchol)
• colestipol (Colestid)
• diabetes medications
• digoxin (Digitek, Lanoxin)
• estrogens (birth control, hormone replacement therapy)
• theophylline (Theo-24, Theobid, Theo-Dur, Theolair, Elixophyllin, Elixophylline, Quibron-T, Uniphyl)
• warfarin (Coumadin, Jantoven)

This is not a complete list of Triostat drug interactions. Ask your doctor or pharmacist for more information.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For injection dosage form:
  • For the treatment of myxedema coma or precoma:
    • Adults—25 to 50 micrograms (mcg) injected into a vein. Doses are normally given at least 4 to 12 hours apart. People with very serious conditions caused by too little thyroid hormone may need higher doses. Lower doses (10 to 20 mcg) may be given to patients with known or suspected cardiovascular disease.
    • Children—Use and dose must be determined by your doctor .

• Tell all of your health care providers that you take this medicine. This includes your doctors, nurses, pharmacists, and dentists.
• Do not run out of Triostat.
• If you have high blood sugar (diabetes), you will need to watch your blood sugar closely.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• This medicine may affect how much of some other drugs are in your body. If you are taking other drugs, talk with your doctor. You may need to have your blood work checked more closely while taking this medicine with your other drugs.
• If you are 65 or older, use Triostat with care. You could have more side effects.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.
• This medicine is not approved for use in children. Talk with the doctor.

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of a weak adrenal gland like a very bad upset stomach or throwing up, very bad dizziness or passing out, muscle weakness, feeling very tired, mood changes, not hungry, or weight loss.
• Signs of high blood sugar like confusion, feeling sleepy, more thirst, more hungry, passing urine more often, flushing, fast breathing, or breath that smells like fruit.
• Chest pain or pressure or a fast heartbeat.
• A heartbeat that does not feel normal.
• Feeling nervous and excitable.
• Headache.
• Bothered by heat.
• Sweating a lot.
• Feeling irritable.
• Shortness of breath, a big weight gain, or swelling in the arms or legs.
• Period (menstrual) changes.

PRESCRIBING INFORMATION

Thyroid hormone drugs are natural or synthetic preparations containing tetraiodothyronine (T4, levothyroxine) sodium or triiodothyronine (T3, liothyronine) sodium or both. T4 and T3 are produced in the human thyroid gland by the iodination and coupling of the amino acid tyrosine. T4 contains four iodine atoms and is formed by the coupling of two molecules of diiodotyrosine (DIT). T3 contains three atoms of iodine and is formed by the coupling of one molecule of DIT with one molecule of monoiodotyrosine (MIT). Both hormones are stored in the thyroid colloid as thyroglobulin and released into the circulation. The major source of T3 has been shown to be peripheral deiodination of T4. T3 is bound less firmly than T4 in the serum, enters peripheral tissues more readily, and binds to specific nuclear receptor(s) to initiate hormonal, metabolic effects. T4 is the prohormone which is deiodinated to T3 for hormone activity.

Thyroid hormone preparations belong to two categories: (1) natural hormonal preparations derived from animal thyroid, and (2) synthetic preparations. Natural preparations include desiccated thyroid and thyroglobulin. Desiccated thyroid is derived from domesticated animals that are used for food by man (either beef or hog thyroid), and thyroglobulin is derived from thyroid glands of the hog.

Triostat (liothyronine sodium injection) (T3) contains liothyronine (L-triiodothyronine or L-T3), a synthetic form of a natural thyroid hormone, as the sodium salt.

The structural and empirical formulas and molecular weight of liothyronine sodium are given below.

L-Tyrosine, 0-(4-hydroxy-3-iodophenyl)-3,5-diiodo-, monosodium salt

In euthyroid patients, 25 mcg of liothyronine is equivalent to approximately 1 grain of desiccated thyroid or thyroglobulin and 0.1 mg of L-thyroxine.

Each mL of Triostat in amber-glass vials contains, in sterile non-pyrogenic aqueous solution, liothyronine sodium equivalent to 10 mcg of liothyronine; alcohol, 6.8% by volume; anhydrous citric acid, 0.175 mg; ammonia, 2.19 mg, as ammonium hydroxide.

Triostat (liothyronine sodium injection) (T3) is indicated in the treatment of myxedema coma/precoma.

Triostat can be used in patients allergic to desiccated thyroid or thyroid extract derived from pork or beef.

The most frequently reported adverse events were arrhythmia (6% of patients) and tachycardia (3%). Cardiopulmonary arrest, hypotension and myocardial infarction occurred in approximately 2% of patients. The following events occurred in approximately 1% or fewer of patients: angina, congestive heart failure, fever, hypertension, phlebitis and twitching.

In rare instances, allergic skin reactions have been reported with liothyronine sodium tablets.

For medical advice about your adverse reactions contact your medical professional. To report SUSPECTED ADVERSE REACTIONS, contact JHP at 1-866-923-2547 or MEDWATCH at 1-800-FDA-1088 (1-800-332-1088) or http://www.fda.gov/medwatch/.

Applies to liothyronine: oral tablet

Other dosage forms:

• intravenous injectable, intravenous solution

Along with its needed effects, liothyronine (the active ingredient contained in Triostat) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Get emergency help immediately if any of the following symptoms of overdose occur while taking liothyronine:

• Arm, back or jaw pain
• changes in appetite
• changes in menstrual periods
• chest pain or discomfort
• chest tightness or heaviness
• cold clammy skin
• confusion
• decreased urine output
• diarrhea
• dilated neck veins
• dizziness
• extreme fatigue
• fainting
• fast, slow, pounding, or irregular heartbeat or pulse
• fever
• hand tremors
• headache
• increased bowel movements
• irregular breathing
• irritability
• leg cramps
• lightheadedness
• menstrual changes
• nausea
• nervousness
• sensitivity to heat
• shortness of breath
• sweating
• swelling of face, fingers, feet, or lower legs
• troubled breathing
• trouble sleeping
• vomiting
• weak pulse
• weight gain
• weight loss
• wheezing