Product description
Synthetic levothyroxine, which is contained in the preparation L-Tyroxin-Farmak, exhibits effects identical to those of the hormone secreted by the thyroid gland. It turns into T3 (triiodothyronine) in peripheral organs, and as an endogenous hormone affects T3 receptors. There is no difference between the functions of endogenous hormone and exogenous levothyroxine.
Indications for use
Treatment of benign euthyroid goiter.
Prevention of relapses after surgical treatment of euthyroid goiter, depending on the level of the hormone in the postoperative period.
As replacement therapy for hypothyroidism.
Suppressive therapy for thyroid cancer.
As an adjunct preparation for antithyroid therapy in hyperthyroidism.
As a diagnostic tool for a thyroid suppression test.
Contraindications
Hypersensitivity to any of the components of the preparation.
Insufficiency of the adrenal glands, pituitary insufficiency, thyrotoxicosis, which have not been treated.
Acute myocardial infarction, acute myocarditis, acute pancarditis.
Combined therapy with levothyroxine and antithyroid preparations during pregnancy is not prescribed.
Method of administration and dosage
For the treatment of each individual patient, depending on his individual needs, the preparation L-Tyroxin-Farmak exists in tablets containing 25 μg, 50 μg, 100 μg of levothyroxine sodium.
Dosing information is only a guideline.
The daily dose is determined individually, depending on laboratory parameters and the clinical picture of the disease.
Since an increase in T4 and fT4 concentrations was observed in a certain number of patients during therapy with levothyroxine, the basal concentration of thyroid-stimulating hormone in the blood serum is a more reliable indicator for further dose adjustment.
Thyroid hormone therapy should be started at a low dose and gradually increased (every 2-4 weeks) to the required therapeutic dose.
Children. For newborns and infants with congenital hypothyroidism, where the rapid achievement of a therapeutic effect is very important, the recommended starting dose is 10 to 15 μg / kg of body weight per day for the first 3 months. After that, the dose is adjusted individually, depending on the clinical parameters and the level (TSH).
Elderly patients with coronary heart disease, patients with severe or prolonged hypothyroidism, treatment should be started with extreme caution, with low doses (12.5 μg per day), the dose should be increased to a maintenance dose at long intervals (gradually by 12.5 μg every 2 weeks), regularly monitoring thyroid hormone levels. It should be noted that the administration of doses lower than the optimal one, which provides complete replacement therapy, does not lead to a complete correction of the TSH level.
Experience has shown that taking low doses is sufficient for patients with low body weight and for patients with large nodular goiter.
| Indications | Recommended doses (levothyroxine sodium, mcg / day) |
| Treatment of benign euthyroid goiter | 75-200 |
| Prevention of relapse after surgical treatment of euthyroid goiter | 75-200 |
In the replacement therapy of hypothyroidism in adults: initial dose; maintenance dose | 25-50 100-200 |
In the replacement therapy of hypothyroidism in children: the initial dose; maintenance dose | 12.5 * -50 100-150 mcg / m2 body surface |
| As an adjunct preparation for antithyroid therapy of hyperthyroidism | 50-100 |
| Suppressive therapy for thyroid cancer | 150-300 |
* - take in the appropriate dosage.
The daily dose can be taken at one time.
Take the daily dose in the morning on an empty stomach, 30 minutes before meals, with a small amount of water (half a glass of water).
For infants, the daily dose of the preparation should be given at one time, 30 minutes before the first feeding. Dissolve the tablet in water until a suspension is obtained, which should be prepared immediately before taking the preparation and used after adding a small amount of liquid.
L-Thyroxin-Farmak should be used throughout life as a replacement therapy for hypothyroidism, after surgical interventions (strumectomy or thyroidectomy), as well as to prevent relapses after removal of euthyroid goiter. To prescribe complex therapy with thyreostatics after reaching the euthyroid state.
With a benign form of euthyroid goiter, the duration of treatment is from 6 months to 2 years. If the condition does not improve after treatment, surgery or radioactive iodine therapy should be prescribed.
Overdose
An increase in the level of T3 (triiodothyronine) is a reliable indicator of preparation overdose, more than an increase in the levels of T4 and fT4 (free) in the blood serum.
As a result of an overdose, symptoms characteristic of an increase in metabolism may appear (see the section "Adverse reactions").
In case of overdose, discontinue use of the preparation and conduct laboratory tests.
For symptoms that manifest as pronounced beta-sympathomimetic effects, such as tachycardia, anxiety, nervous irritability, hyperkinesia, beta-blockers are prescribed. If the dose is significantly exceeded, plasmapheresis is recommended.
In some cases, in patients prone to seizures, seizures may develop when the individual permissible dose of the preparation has been exceeded.
An overdose of levothyroxine can cause symptoms of hyperthyroidism and lead to acute psychosis, especially in patients at risk of developing psychotic disorders.
There are several reports of sudden coronary death in patients who have abused (exceeded the recommended dosage) levothyroxine for many years.
Special instructions
Use during pregnancy or lactation
During pregnancy or lactation, treatment with a preparation prescribed for hypothyroidism should be continued. During pregnancy, there may be a need to increase the dose of the preparation. Since an increase in serum TSH levels can occur as early as 4 weeks of gestation, pregnant women taking levothyroxine should have their TSH levels checked during each trimester. Serum TSH levels in pregnant women should be within the appropriate range for each trimester. To correct elevated serum TSH levels, the dose of levothyroxine should be increased. Since postnatal TSH levels correspond to the values available before fertilization, the dose of levoteraxine should be adjusted immediately after delivery in accordance with the dose before pregnancy. The required serum TSH level should be established 6-8 weeks after delivery.
Pregnancy.
There are no data on teratogenicity and / or fetotoxicity when taking the preparation in the recommended therapeutic doses. Taking very high doses of levothyroxine during pregnancy can negatively affect the fetus and the baby's postnatal development.
Combined therapy with levothyroxine and antithyroid preparations during pregnancy is not prescribed for the treatment of hyperthyroidism, since this combination of preparations requires the administration of higher doses of antithyroid preparations that can pass through the placenta and can cause the development of hypothyroidism in the newborn. A thyroid suppression test is not performed during pregnancy, since the use of radioactive substances is contraindicated during pregnancy.
Lactation.
Levothyroxine is excreted in breast milk during breastfeeding, however, when the preparation is used in the recommended therapeutic doses, the concentration level of the preparation in breast milk is insufficient for the development of hyperthyroidism or suppression of TSH secretion in the infant.
Children
The preparation is used in children from birth.
The ability to influence the reaction rate when driving or driving other mechanisms
There is no data on the possible effect on the ability to drive vehicles or work with complex mechanisms. However, since levothyroxine in its action is identical to the natural thyroid hormone, the effect of L-Tyroxin-Farmak on the reaction rate when driving vehicles or other mechanisms is not expected.
Compound
active substance: levothyroxine sodium;
1 tablet contains levothyroxine sodium in terms of 100% dry matter 50 μg;
auxiliary substances: potato starch, lactose monohydrate, sucrose, heavy magnesium carbonate, magnesium stearate, povidone.
Storage conditions
Store in its original packaging at a temperature not exceeding 25 ° C.
Keep out of the reach of children.
Shelf life is 3 years.
Do not use the preparation after the expiration date indicated on the package.