Liothyronine 25mcg

Liothyronine general information

What is Liothyronine used for?

Liothyronine tablets 25mcg (also known as Cytomel) are used in the management of severe chronic thyroid deficiency or hypothyroidism in which the thyroid gland does not make enough thyroid hormone needed to regulate the body’s growth and metabolism.  This may be due to underactive thyroid; or as a result of an autoimmune disease (where the immune system is directed against self) called Hashimoto disease; or because the pituitary gland does not produce enough thyroid stimulating hormone.  Liothyronine tablets 25mcg are used to help to relieve the symptoms of hypothyroidism (also known as myxoedema), including, tiredness, muscle weakness, cramps, feeling the cold, a slow heart rate, dry and flaky skin, hair loss, a deep husky voice and weight gain; also myxoedema coma, which is a serious complication of hypothyroidism.  Liothyronine tablets 25mcg are also used treat or prevent thyroid goitre, in which the thyroid becomes enlarged to compensate for low levels of thyroid hormone and is often due to iodine deficiency.   Liothyronine tablets 25mcg are also used to increase low thyroxine levels (in addition to another drug called carbimazole), which may result from treatment for thyrotoxicosis or overactive thyroid gland, in which overproduction of thyroid hormones is the result of autoimmune disease (Graves disease) or inflammation of the thyroid gland.  Liothyronine sodium tablets can be used in patients allergic to desiccated thyroid or thyroid extract derived from pigs or cows.

How does Liothyronine work?

Liothyronine tablets 25mcg contain liothyronine (also known as triiodothyronine or T₃), a synthetic form of naturally occurring (endogenous) thyroid hormone.  The major effect of exogenous thyroid hormones is to increase the metabolic rate of body tissues.  The thyroid gland produces mainly thyroxine (levothyroxine or T₄) and a small amount of liothyronine, however, the major form of thyroid hormone in the blood is T₄ which circulates bound to protein and is therefore not active.  When it reaches the target tissue, T₄ is released and converted to T₃ which is 3-4 times more potent than T₄ and acts rapidly by interacting with a specific receptor inside cells to stimulate proteins needed to manage and regulate a variety of processes, including how the body regulates temperature, metabolises nutrients and controls growth and development.  Liothyronine tablets 25mcg are particularly useful for treating severe and acute symptoms of thyroid hormone deficiency (hypothyroid state) because of the rapid (occurring within a few hours), intensive and short-lived effect (24 to 48 hours) of liothyronine (T₃ ).

What does Liothyronine contain?

Liothyronine tablets 25mcg contain the active ingredient liothyronine (L-triiodothyronine or LT3), a synthetic form of a natural thyroid hormone as the sodium salt, used to treat thyroid deficiency or hypothyroidism. Sigma Liothyronine also contains the inactive ingredients calcium sulfate dihydrate, corn starch, gelatin, magnesium stearate and mannitol.

Treating underactive thyroid (hypothyroidism) with Liothyronine

Liothyronine tablets 25mcg contain triiodothyronine or (T₃), which is the more active form of naturally occurring thyroid hormone, and is used in the management of severe chronic thyroid deficiency or hypothyroidism in which the thyroid gland does not make enough thyroid hormone needed to regulate the body’s growth and metabolism.  Liothyronine tablets 25mcg are used to help to relieve the symptoms of hypothyroidism (also known as myxoedema), including, tiredness, muscle weakness, cramps, feeling the cold, a slow heart rate, dry and flaky skin, hair loss, a deep husky voice and weight gain; also to treat coma due to myxoedema; and to treat or prevent thyroid goitre, an enlarged thyroid gland.  Liothyronine tablets 25mcg are also used to increase low thyroxine levels which may result from treatment for thyrotoxicosis or overactive thyroid gland, in which overproduction of thyroid hormones is the result of autoimmune disease (Graves’ disease) or inflammation of the thyroid gland.  The thyroid gland produces mainly thyroxine (levothyroxine or T₄) and a small amount of liothyronine (T₃).  When it reaches the target tissue, T₄ is converted to T₃ where it interacts with a specific receptor inside cells to stimulate proteins needed to manage and regulate a variety of processes, including how the body regulates temperature, metabolises nutrients and controls growth and development. 

What are the side effects of Liothyronine?

Most of the side effects experienced with taking Liothyronine tablets 25mcg indicate that the dose is too high and may need adjusting.  These include: headache, palpitations, sleep problems (insomnia), feeling nervous or irritable sweating, flushing, appetite changes, weight loss, muscle weakness/cramps, tremors.  

When should Liothyronine not be used?

You should not use Liothyronine tablets 25mcg if you:

• are allergic to Liothyronine or any ingredients in Liothyronine sodium tablets
• are looking for a treatment for obesity or to help you lose weight; this is not a weight loss product
• are pregnant, planning to become pregnant or breast-feeding
• have a history of chest pain, heart attack, heart blood vessel problems, or other heart problems, particularly in the elderly
• have adrenal gland problems
• are a diabetic taking antidiabetics or insulin, without discussion with your doctor, as Liothyronine tablets may affect your glucose tolerance
• are taking other medications that may interact with Liothyronine tablets, such as anticonvulsants like phenytoin and carbamazepin, cardiac glycosides like digoxin, cholesterol-lowing drugs containing cholestyramine, tricyclic antidepressants like amitriptyline, anticoagulants like warfarin, oral contraceptives containing oestrogen, insulin or oral hypoglycemic for diabetes

What medications interact with Liothyronine?

Several medications interact with Liothyronine tablets 25mcg and should either not be taken while you are taking Liothyronine or only after discussion and instruction from your doctor:

• Drugs that cause a serious reaction with Liothyronine: tricyclic antidepressants like amitriptyline, anticoagulants like warfarin, cardiac glycosides like digoxin
• Drugs that affect Liothyronine: cholesterol-lowing drugs containing cholestyramine, anticonvulsants like phenytoin and carbamazepin, oral contraceptives containing oestrogen
• Drugs that are affected by Liothyronine: insulin or oral hypoglycemic for diabetes

How should Liothyronine be taken?

You should take your Liothyronine tablets 25mcg with a glass of water with or without food.  The dose you take and how often depends on your condition and should be as recommended by your doctor; usually every 8 hours, or 2-3 times a day, and your dose may be increased after the first week.  You may need to take your Liothyronine tablets 25mcg for a few weeks before you see an improvement and you should continue to take your Liothyronine tablets 25mcg for as long as recommended by your doctor, which may be for life.

How long should you take Liothyronine?

You may need to take your Liothyronine tablets 25mcg for a few weeks before you see an improvement and you should continue to take your Liothyronine tablets 25mcg for as long as recommended by your doctor, which may be for life

Missed dose of Liothyronine

If you miss a dose of Liothyronine tablets 25mcg take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not take a double dose.

How should Liothyronine be stored?

You should store your Liothyronine tablets 25mcg below 25°C in a cool dry place.