Levotiroksin sodium - instructions for use, dose, side effects, contraindications

The synthetic thyroid hormone levothyroxine compensates for the deficiency of thyroid hormones. Strengthening the need for oxygen in tissues, stimulates their growth and differentiation, increases the level of basal metabolism: proteins, carbohydrates, fats. Small doses of the drug are anabolic, and large - catabolic effect.Strengthening of energy processes has a positive effect on the functions of the cardiovascular and nervous system, kidneys and liver.

Pharmacokinetics:

After oral administration, an empty stomach absorbs up to 80% in the upper part of the small intestine. The maximum concentration in blood plasma is reached after 6 hours. The connection with plasma proteins is 99%.

Therapeutic effect develops 3-5 days after the beginning of the admission. Metabolism in the liver, muscles, kidneys, brain tissue.

The half-life is 6-7 days. Elimination by the kidneys.

Indications:

It is used for the treatment of hypothyroidism, treatment of eutheroid goiter, thyrotoxicosis, as well as for the prevention of relapse after resection of the thyroid gland.

ICD-10

IV.E00-E07.E03.9 Hypothyroidism, unspecified

IV.E00-E07.E05.2 Thyrotoxicosis with a toxic multinodular goiter

IV.E00-E07.E05 Thyrotoxicosis [hyperthyroidism]

IV.E00-E07.E06.3 Autoimmune thyroiditis

II.C73-C75.C73 Malignant neoplasm of thyroid gland

IV.E00-E07.E01.1 Multinodular (endemic) goiter associated with iodine deficiency

Contraindications:

Acute myocardial infarction, myocarditis, thyrotoxicosis, Dühring's disease (herpeticomorphic dermatitis).

Individual intolerance.

Carefully:Ischemic heart disease, heart failure, sugar and diabetes insipidus, malabsorption syndrome.

Pregnancy and lactation:

Recommendations for FDA - Category A. In pregnancy, the prescribed treatment should continue, with a dose adjustment: in the II-III trimesters, the dose increases by 25% of the initial dose. When breastfeeding, the dose of the drug is corrected by the attending physician.

Dosing and Administration:

Use in children

Premature babies with a body weight of less than 2 kg: an initial dose of 25 mcg per day, with a gradual increase (4-6 weeks) to 50 mcg per day.

Newborns: 10 mcg / kg per day, with an increase of 5 mcg / kg every 2 weeks; the average dose is 25-37.5 μg / kg per day.

Children 6-12 months: 5-6 mcg / kg per day.

1-5 years: 3-5 mcg / kg per day.

6-10 years: 4-5 μg / kg per day.

Older than 10 years: 2-3mkg / kg per day.

12-18 years: 50-100 mcg / day.

Adults

Once inside for 30 minutes before breakfast, without chewing. The initial dose of 12.5-25 mcg per day. Gradual increase in the dose every 1-2 weeks until maintenance: 75-125 mcg per day. Reception regular, cancellation or correction of a dose is carried out on the basis of laboratory data.

Intravenous or intramuscular: 50-100 mcg once a day.

The highest daily dose: 125 mcg.

The highest single dose: 125 mcg.

Side effects:

Perhaps the development of craniostenosis in newborns and the development of osteoporosis in women during menopause.

Allergic reactions.

Overdose:Symptomatic of thyrotoxicosis: tachycardia, finger tremors, exophthalmos, weight loss, hyperhidrosis.

Treatment: reduction of the dose of the drug. In cases of acute poisoning, plasmaphoresis is indicated.

Interaction:

Simultaneous use with salicylates, dicumarol, clofibrate, phenytoin, furosemide enhances the effect of the drug.

The drug potentiates the effect of indirect anticoagulants.

Increases the need for hypoglycemic drugs, including insulin.

Reduces the negative dromotropic and inotropic effect of cardiac glycosides.

Simultaneous use with estrogens increases the amount of thyroxine-binding globulin.

Special instructions:

Before prescribing the drug, a check should be made for the hypofunction of the adrenal cortex.

Instructions

Levothyroxine sodium (Levothyroxinum natrium)