1 tabl contains 50 μg or 100 μg of sodium levothyroxine.
Action:
Synthetic sodium salt of levorotatory thyroxine. Thyroxine is a natural hormone produced by the thyroid gland and transformed in peripheral tissues into a more active hormone - triiodothyronine (T3). Thyroid hormones are essential for proper growth and development of the body, especially for the development of the nervous system. They increase the resting, basic metabolism of the body, have a stimulating effect on the heart, skeletal muscles, liver and kidneys. Thyroid hormones increase lipolysis and carbohydrate utilization. After oral administration, the absorption of thyroxine is incomplete and variable, especially in the presence of food. The absorption of the drug is greater after administration on an empty stomach. Almost completely bound to plasma proteins. The metabolism of thyroxine depends mainly on its conversion by deodorisation to the active metabolite - triiodothyronine. T0,5 is about 7 days. 20-40% of the drug is excreted in the faeces, 30-55% - in the urine.
Contraindications:
Hypersensitivity to the components of the preparation. Thyrotoxicosis.
Precautions:
Especially cautiously use in the elderly and in patients with symptoms of heart failure, as well as in patients with features of myocardial infarction or ischaemia in the ECG and in the case of diabetes and diabetes insipidus.
Pregnancy and lactation:
The drug can be used during pregnancy. Thyroxine is secreted into low-concentration female foods, which, however, may affect the outcome of screening tests to detect congenital hypothyroidism in the newborn.
Side effects:
The following symptoms indicate that the dose used is too high: hypersensitivity reactions - rash and itching of the skin, increased appetite, abdominal cramps, nausea, diarrhea, vomiting, increased excitability, anxiety, insomnia, tremors, convulsions, headache , angina pectoris, cardiac arrhythmia, tachycardia, palpitations, increased blood pressure, heart failure, myocardial infarction, shortness of breath, hot flushes and sweats, baldness, skeletal muscle cramps, muscle weakness, decreased bone density, irregular menstruation, impaired fertility , fatigue, heat intolerance, fever, significant weight loss. The use of too high doses may cause premature ossification of the cranial sutures in infants, premature overgrowth of the epiphyseal bone in children, and low growth in adulthood. Rare cases of benign intracranial hypertension have been registered (especially in children).
Dosage:
Orally. Adults: The starting dose is 50-100 μg per day on an empty stomach, which should be increased at 4-6 weeks intervals by 50 μg to achieve the clinical and biochemical features of euthyreosis. This usually requires a dose of 100-200 μg per day. In patients over the age of 50 years, an initial dose of more than 50 μg per day should not be used. In the case of heart disease, 50 μg should be used every other day, the daily dose should be increased by 50 μg every other day, preferably at 4-week intervals. Children with congenital hypothyroidism: the starting dose is 50 μg every other day; The dose should be increased by 50 μg every other day, at 2-4 weeks intervals, until the optimal response to treatment is achieved. The same applies to cases of juvenile mucous edema with the proviso that the starting dose for children over 1 year may be 2.5-5 μg / kg / day. To determine the dose to be prescribed for a given patient, the calculated daily dose should be rounded to the nearest multiple of 25 μg. The tablets should not be crushed or divided.
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