A thyroxine

 A thyroxine
 A thyroxine - a drug for the treatment of diseases related to insufficient production of thyroid hormones.

Pharmacological action

A thyroxine affects the metabolism and development of tissues, in small doses, manifests itself as an anabolic (muscle helps to increase the volume), in moderate doses activates fat, protein, carbohydrate metabolism, a positive effect on the nervous system, blood vessels, heart.

Application A thyroxine in large quantities makes it possible to suppress the production of hormones of the pituitary gland and hypothalamus. At the same time there are reviews of A thyroxine, that its effect is manifested through 7-12dn, and the same amount is saved after its cancellation.

In hypothyroidism - a condition associated with low levels of thyroid hormones, thyroxine action A has been observed for 3-5 days. Diffuse goiter disappear or significantly reduced after 3-6 months of taking L thyroxine.

Product form


Indications for admission A thyroxine

Effectively hypothyroidism, have evolved for different reasons, with insufficient production of thyroid hormones, in benign euthyroid goiter, thyroid cancer.

A thyroxine often include complex treatment of autoimmune thyroiditis, Graves' disease, is used to test the functionality of the thyroid gland.

A Allowed to take thyroxine during pregnancy - for the treatment of hypothyroidism.

As a means of adjuvant therapy drug used to treat hyperthyroidism after it reaches euthyroid state.

A Guide thyroxine: how to use

For the treatment of hypothyroidism in an initial stage taking 25-100mkg A thyroxine per day. The maintenance dose in this disease - 125-250mkg. For the treatment of children the recommended starting dose is 12 5-50mkg supporting - 100-150mkg / 1 sq.m. body surface.

Babies up to six months in hypothyroidism congenital appoint 8-10mkg / kg / day for children 6-12mes. - 6-8mkg / kg / day; children 1-5l - 5-6mkg / kg / day for children 6-12l - 4-5mkg / kg / day.

For the treatment of endemic goiter A thyroxine administered in a dosage 50mkg / day, gradually increasing it to 100-200mkg.

When euthyroid goiter and its prevention after resection of children prescribed 12 5-150mkg / day for adults - 75-200mkg / night ,.

During further treatment thyreostatics A thyroxine according to the instructions prescribed in the dosage 50-100mkg / day.

For the test prescribed a single dose of L thyroxin - 3mg, after a light breakfast or on an empty stomach one week before the isotope study of the thyroid gland.

In malignant tumors in the thyroid gland after surgery drug taking 150-300mkg / day.

Patients with cardiovascular pathologies A thyroxine according to the instructions prescribed in small quantities, the dosage is increased gradually, based on data held regularly electrocardiographic studies.

Older patients need long-term treatment with the L thyroxine prescribe a starting dose of 25mkg and within 6-12 weeks, it was raised to support the full dose.

A thyroxine during pregnancy (in the 2nd, 3rd trimester) administered in a 25% increase dosage.

Side effects

A thyroxine can cause allergy: itching and skin rashes.

High doses of the drug can cause the development of hyperthyroidism, which is accompanied by dysmenorrhea, diarrhea, change in appetite, headache, tremor, arrhythmia, tachycardia, irritability, nervousness, sweating, muscle cramps in the legs, vomiting, weight loss.

Judging by the reviews, L thyroxine insufficiently effective dosage can cause hypothyroidism, in which there is dryness, swelling of the skin, dysmenorrhea, headache, constipation, weakness, weight gain, lethargy, myalgia, lethargy, drowsiness.

In children, the drug can cause brain pseudotumor.

In overdose begins thyrotoxic crisis, for relief which injected steroids, prescribed beta-blockers, plasmapheresis is performed.  A thyroxine is produced in the form of tablets


A thyroxine should not be taken at its intolerance with caution means prescribed for various diseases of the heart, blood vessels, or diabetes insipidus, adrenal insufficiency or pituitary insufficiency, malabsorption syndrome, hyperthyroidism in the past, severe prolonged thyroid hypofunction cancer.

Starting treatment with L thyroxine during pregnancy should be excluded hypothalamic, pituitary hypothyroidism.

Reviews of A thyroxine indicate it reduces the effectiveness of oral drugs that reduce blood sugar, insulin, cardiac glycoside, increases the effect of indirect anticoagulants, tricyclic antidepressants.

A concentration of thyroxine in the blood increase furosemide, salicylates, phenytoin, clofibrate.

On the pharmacokinetics of the drug affect ethionamide, amiodarone, beta-blockers, chloral hydrate, levodopa, carbamazepine, dopamine, lovastatin, diazepam, somatostatin, metoclopramide, aminoglutethimide, antithyroid drugs.