L Thyroxine: what helps, instructions for use

50193 06 August

IMPORTANT!

The information in this section cannot be used for self-diagnosis and self-treatment.
In case of pain or other exacerbation of the disease, diagnostic tests should be prescribed only by the attending physician. To make a diagnosis and properly prescribe treatment, you should contact your doctor. We remind you that independent interpretation of the results is unacceptable, the information below is for reference only
T4 free, Free Thyroxine, FT4:
indications for use, rules for preparing for the test, interpretation of the results and normal indicators.

pharmachologic effect

L Thyroxine is a substance of thyroid hormones. The active element of the drug has a similar therapeutic effect as the thyroid gland’s own compounds - triiodothyronine and thyroxine. Once in the body, sodium levothyroxine is converted into liothyronine, which has a direct effect on human growth and development, as well as the regulation of metabolism.

It is L Thyroxine that has the ability to influence oxidative metabolism in mitochondria and control the amount of cations inside and outside cells.

The pharmacological effect of the drug is explained by its dose. When taking the drug in a small dosage, anabolic processes occur in the body, and at a high dose, acceleration of oxidative reactions and metabolism is observed, cells and tissues become more demanding of oxygen, and improvement in the functioning of the heart, blood vessels and nervous system is also observed.

The result of therapy when taking the drug can be noticed after 5 days. Over the course of 3-6 months, the symptoms of diffuse goiter are completely suppressed.

The drug is rapidly absorbed after oral administration. Excreted through the kidneys and intestines.

Types of thyroid hormones

The thyroid gland produces two hormones: thyroxine (T4) and triiodothyronine (T3). They have common physiological properties, but differ in the number of iodine atoms in the molecule. Both Thyroxine and triiodothyronine are derivatives of tyrosine. The production of thyroid hormones is regulated by the hypothalamic-pituitary system.

When talking about the two main thyroid hormones, one cannot fail to mention TSH or thyroid-stimulating hormone of the anterior pituitary gland. It acts on specific receptors that are located on the epithelium of the thyroid gland and stimulates the synthesis of thyroxine.

Thus, TSH, T3 and T4 are closely related. The higher the concentration of the thyroid-stimulating hormone TSH, the lower the production of thyroid hormones of the thyroid gland - T4 and T3. At the early stage of endocrine diseases, laboratory diagnostic results may not show insufficient or excessive production of thyroid hormones, but the TSH level may indicate the presence of certain disorders. This allows for in-depth diagnosis to begin treatment as early as possible.

Indications for Thyroxine

As a rule, Thyroxine is included in the basis of hormonal replacement treatment for decreased thyroid function. In addition, taking the medicine is relevant for the following conditions:

1. Hypothyroidism of various origins.
2. ​Excess body weight and pronounced signs of cretinism, provoking the appearance of thyroid hypothyroidism.
3. ​Cerebral-pituitary pathological conditions.
4. ​Prevention of the occurrence of nodular goiter due to surgery on the organ.
5. Therapy of diffuse goiter.
6. ​Treatment of malignant tumor of the thyroid gland.
7. ​Graves pathology.
8. Euthyroid proliferation of the gland.

Signs of decreased and increased thyroid hormone levels

When the production of thyroid hormones is low, hypothyroidism develops. The disease can occur for a long time without significant symptoms.

The main manifestations of low levels of thyroid hormones:

• decreased performance;
• the appearance of daytime drowsiness and some inhibition of reactions;
• frequent illnesses due to weakened immune defenses;
• swelling in the legs and arms;
• disruption of the female menstrual cycle;
• instability to low temperatures and increased sensitivity to cold;
• deterioration of skin and hair condition.

When the concentration of thyroid hormones increases, the following signs appear:

• weight loss;
• cardiopalmus;
• unstable mental state;
• trembling of fingers;
• increased sweating;
• formation of a goiter in the neck area;
• physical weakness and high fatigue.

Contraindications

Absolute contraindications to the use of Thyroxine are:

1. ​Acute myocardial infarction.
2. ​Severe inflammatory lesions of the heart.
3. Thyrotoxicosis, which has not previously been treated.
4. ​Galactose deficiency.
5. Impaired absorption of substances by the intestinal walls.
6. ​Individual intolerance to the active substance.
7. ​Kypocorticism.

It is necessary to take the drug with extreme caution in patients suffering from severe diseases of the heart and blood vessels, diabetes mellitus, and a severe form of hypothyroidism with a prolonged course of the process. In this case, patients need to change the therapeutic dose and duration of the therapeutic course.

Use of the drug L-thyroxine Berlin-Chemie

The daily dose of the drug is set individually based on clinical and laboratory examination data. If residual thyroid function is preserved, the dose of replacement therapy may be slightly lower than usually prescribed. Particular caution is required when starting treatment with thyroid hormones in elderly patients, with coronary artery disease, severe hypothyroidism, or in cases where decreased thyroid function has been observed for a long time. In these cases, it is necessary to choose a lower initial dose and gradually increase it with frequent monitoring of thyroid hormone levels. In case of insufficient body weight and the presence of a large nodular goiter, a low dose is sufficient. Unless otherwise prescribed, the following dosage recommendations exist: Adults Hypothyroidism. The initial dose is 25–50 mcg/day, maintenance dose is 100–200 mcg/day (the dose is increased by 25–50 mcg at intervals of 2–4 weeks). Prevention of goiter relapse: 75–200 mcg/day. Benign goiter with a euthyroid state of function: 75–200 mcg/day. Concomitant therapy in the treatment of hyperthyroidism with thyrestatics - 50–100 mcg/day. Children. The starting dose for children is 12.5-50 mcg, and for infants - 25-50 mcg. When prescribing a replacement dose during long-term therapy, the child’s age and body weight are taken into account, among other indicators. The following are approximately recommended doses:

Due to the special shape of the tablet, it can be divided by placing the tablet on a hard surface with the division notch facing upward and pressing it with your finger from above in a perpendicular direction. The daily dose is taken once in the morning on an empty stomach at least 30 minutes before meals. The tablets are taken without chewing and washed down with a small amount of water (1/2 cup). For infants, the daily dose is prescribed no later than 30 minutes before the first feeding. To do this, the tablets are dissolved in a small amount of water, and the resulting mixture (prepare immediately before use!) is given along with a small amount of liquid. Duration of therapy: for hypothyroidism, in most cases, throughout life; in the treatment of euthyroid goiter, as well as for the purpose of preventing goiter relapse - from several months, years and until the end of life; as concomitant therapy in the treatment of hyperthyroidism - depending on the duration of administration of the thyreostatic agent.

Side effects of L Thyroxine

If you take the drug under the vigilant supervision of a doctor and follow all his recommendations, taking the drug does not cause any side effects. Otherwise, symptoms of an allergic reaction are observed - skin rash, hyperemia, itching, urticaria.

Other symptoms occur with a high dose or incorrect treatment tactics. They appear rarely and represent the following conditions:

1. ​Headache, tremors of extremities, anxiety, excitement, sleep disturbance.
2. ​Cardiac disorder - arrhythmia, palpitations, angina pectoris, tachycardia.
3. ​Dyspeptic manifestations.
4. Pathological course of menstruation.
5. ​Allergic symptoms.
6. ​Excessive sweating, weight loss, fever, constant weakness, fever.

When should you take a general T4 test?

1. Suspicion of hypo- or hyperthyroidism;
2. Changes in the size of the thyroid gland;
3. Uncontrolled weight loss;
4. Prolonged depression or irritability;
5. Increase or decrease in the concentration of thyroid-stimulating hormone;
6. Routine examination during pregnancy;
7. Examination in the absence of menstruation or suspected infertility;
8. Deviations in the development of children;
9. Control in the treatment of gland diseases;
10. Examination of persons with a predisposition to thyroid diseases.

Instructions for use of L Thyroxine

According to the instructions, the drug should be taken on an empty stomach half an hour to an hour before meals, washed down with small amounts of still water. It is recommended not to chew the tablets. The therapeutic dose and course duration are determined by a specialist depending on the clinical indications.

As a replacement treatment, the drug is prescribed to patients under 55 years of age who do not have problems with the cardiovascular system at a dose of 1.6-1.8 mcg/kg. If there are any diseases and the patient is over 55 years old, the therapeutic dosage is halved.

For the treatment of congenital hypothyroidism, the dose of the drug is calculated taking into account the weight and age of the patient. The drug can be prescribed to children from the first days of life. As a rule, for such a condition, Thyroxine tablets are used for life.

For the treatment of thyrotoxicosis, the drug is simultaneously combined with antithyroid drugs after achieving the euthyroid process.

Instructions for use L-THYROXIN 100 BERLIN-CHEMIE (L-THYROXIN 100 BERLIN-CHEMIE)

Cholestyramine and colestipol inhibit the absorption of levothyroxine, so they should be taken no earlier than 4 - 5 hours after taking L-Thyroxine 50 Berlin-Chemie.

Absorption of levothyroxine may be reduced by concomitant use of aluminum-containing antacids that bind stomach acid, calcium carbonate and iron-containing drugs. Therefore, L-Thyroxine 50 Berlin-Chemie should be taken at least two hours before taking these drugs.

Sevelamer may reduce the bioavailability of levothyroxine. Therefore, L-Thyroxine 50 Berlin-Chemie should be taken at least 1-3 hours before taking sevelamer.

Propylthiouracil, glucocorticoids, β-blockers, and radiocontrast agents containing iodine inhibit the conversion of T4 to T3.

Due to its high iodine content, amiodarone can cause both hyperthyroidism and hypothyroidism. Particular attention should be paid in the case of nodular goiter with possible undiagnosed functional autonomy of the thyroid gland.

Rapid intravenous administration of phenytoin can lead to increased levels of free levothyroxine in the blood plasma and, in some cases, alleviate the development of arrhythmia.

Salicylates, dicoumarol, high doses of furosemide (250 mg), clofibrate and other substances may displace levothyroxine from plasma protein binding sites and thus lead to an increase in plasma free levothyroxine levels.

Sertraline and chloroquine/proguanil reduce the effectiveness of levothyroxine and increase serum TSH levels.

Barbiturates and other drugs with enzyme-inducing effects on the liver may increase the hepatic clearance of levothyroxine.

The need for levothyroxine may be increased during the period of taking estrogen-containing contraceptives or during hormone replacement therapy in the postmenopausal period.

Products containing soy may impair the absorption of L-Thyroxine 50 Berlin-Chemie in the intestine. At the beginning and especially at the end of the use of a soy-containing diet, adjustment of the dose of L-Thyroxine 50 Berlin-Chemie may be necessary.

Levothyroxine may weaken the hypoglycemic effect of antidiabetic drugs. Therefore, mainly at the beginning of thyroid hormone therapy in diabetics, regular monitoring of blood glucose levels is necessary. The dose of the antidiabetic drug may need to be adjusted.

Levothyroxine may enhance the effect of coumarin derivatives by displacing them from sites of binding to plasma proteins. Therefore, during concomitant treatment, regular monitoring of blood clotting parameters is required and the dose of the anticoagulant may need to be adjusted.