Levothyroxine Sodium Tablets

Pharmacology: The synthetic levothyroxine contained in this product is identical to the thyroxine naturally secreted by the thyroid gland. Like endogenous hormones, it is converted to T3 in peripheral organs and then exerts its specific effects by binding to T3 receptors. The human body cannot distinguish between endogenous and exogenous levothyroxine. Toxicology: Levothyroxine has very mild acute toxicity. Chronic toxicity studies in animals of different species (rats, dogs) have found that when rats are given high doses of levothyroxine sodium, signs of liver disease, an increased incidence of spontaneous nephropathy, and changes in organ weights occur. Only very small amounts of ineffective thyroid hormones cross the placenta. Sufficient human test data have shown that the use of levothyroxine at different stages of pregnancy has no toxic effects on the fetus and does not cause malformations. There are no reports that this product impairs male or female fertility, nor is there any evidence that fertility impairment is related to this product. There is no information on the mutagenicity of this product. So far, there is no evidence that thyroid hormones can cause genomic changes that harm the offspring. No long-term animal studies have been conducted on the carcinogenicity of levothyroxine.

Levothyroxine sodium. Its chemical name is: O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-L-tyrosine monosodium salt. Molecular weight: C15H25I4NNaO4·xH2O

This product is white or off-white tablets.

It is suitable for long-term replacement treatment of congenital hypothyroidism (cretinism) and hypothyroidism caused by various reasons in children and adults. It can also be used for suppression (and replacement) treatment of simple goiter, chronic lymphocytic thyroiditis, and thyroid cancer surgery. It can also be used for suppression tests to diagnose hyperthyroidism.

Oral administration for adults: Generally, the initial daily dose is 25-50 μg, and the maximum dose is no more than 100 μg. The dose can be increased by 25-50 μg every 2-4 weeks until normal metabolism is maintained. The general maintenance dose is 50-200 μg/day.

If the drug is taken as directed and clinical and laboratory indicators are monitored, adverse reactions generally do not occur. If the individual's tolerance dose is exceeded or the drug is overdosed, especially due to a rapid increase in the dose at the beginning of treatment, the following clinical symptoms of hyperthyroidism may occur, including: tachycardia, palpitations, arrhythmia, angina, headache, muscle weakness and cramps, flushing, fever, vomiting, menstrual disorders, pseudotumor cerebri, tremor, restlessness, insomnia, sweating, weight loss and diarrhea.

Those who are highly sensitive to this product and its excipients. Untreated adrenal insufficiency, pituitary insufficiency and thyrotoxicosis. Treatment with this product should not be started during the acute myocardial infarction period, acute myocarditis and acute pancarditis. This product should not be used in combination with antithyroid drugs to treat hyperthyroidism during pregnancy.

Precautions for children: For neonates and children with hypothyroidism or cretinism, refer to the following table for dosage: Recommended dosage (daily) or follow doctor's advice: Age Daily dosage (mg) By weight (mg/kg) 0-6 months 25-50 micrograms (8-10 micrograms/kg body weight) 7-12 months 50-70 micrograms (6-8 micrograms/kg body weight) 2-5 years old 75-100 micrograms (5-6 micrograms/kg body weight) 6-12 years old 100-150 micrograms (4-5 micrograms/kg body weight) 12 years old and above 15 Precautions for pregnancy and lactation: During thyroid replacement therapy, close monitoring is required to avoid low or high thyroid function, so as to avoid adverse effects on the fetus and infant. Trace amounts of thyroid hormone can be excreted from breast milk. Precautions for the elderly: The dosage of levothyroxine sodium tablets must be used with great caution for elderly patients. It should start with a small dose, and the interval between dose increases should be longer, that is, the dose should be increased slowly, and the blood thyroxine level should be monitored regularly.

Antidiabetic drugs: Levothyroxine may reduce the hypoglycemic effect of this type of drug. Therefore, when starting thyroid hormone treatment, the patient's blood sugar level should be monitored frequently, and the dose of antidiabetic drugs should be adjusted if necessary. Coumarin derivatives: Levothyroxine can replace the binding of anticoagulants to plasma proteins, thereby enhancing their effects. Therefore, when starting thyroxine treatment, coagulation indicators should be monitored regularly and the dose of anticoagulants should be adjusted if necessary. Cholestyramine, colestipol: Cholestyramine will inhibit the absorption of levothyroxine sodium, so levothyroxine sodium should be taken 4-5 hours before taking cholestyramine. The situation of colestipol is the same as that of cholestyramine. Aluminum-containing drugs, iron-containing drugs and calcium carbonate: Relevant literature reports that aluminum-containing drugs (antacids, ulcerogen) may reduce the effect of levothyroxine. Therefore

Keep away from light and store in a sealed container below 25℃.

50ug*100s

36 months