L-Thyroxine 100 #100

L-Thyroxine user manual

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Composition

The composition of one tablet of L-Thyroxine may include 25 to 200 μg of levothyroxine sodium.
The composition of the excipients may vary slightly depending on which pharmaceutical company the product is manufactured.

Form of issue

The product is available in tablet form and is delivered to pharmacies in packages No. 25, No. 50 or No. 100.

pharmachologic effect

L-Thyroxine is a thyroid-stimulating drug that is used for hypothyroidism of the thyroid gland (thyroid gland).

Pharmacodynamics and pharmacokinetics

Levotiroksin sodium, which is a part of the tablets, performs the same functions as endogenous (produced thyroid thyroid) thyroxine and triiodothyronine. In the body, the substance is biotransformed to lyotyronine, which in turn penetrates into cells and tissues, influences the mechanisms of development and growth, as well as the course of metabolic processes.
In particular, L-thyroxin is characterized by the ability to affect oxidative metabolism in the mitochondria and selectively regulate the cation flow both in the intracellular space and outside the cell.
The effect of the substance depends on its dosage: the use of the drug in small doses provokes an anabolic effect, in higher doses it affects mainly cells and tissues, increasing the latter's need for oxygen, stimulating oxidative reactions, accelerating the cleavage and exchange of fats, proteins and carbohydrates , activating the functions of the heart, vascular system and the central nervous system.
The clinical manifestation of the action of levothyroxine in hypothyroidism is noted already in the first 5 days after the start of treatment. Over the next 3-6 months, under the condition of continuous use of the drug, the diffuse goiter decreases or completely disappears.
Orally taken levothyroxine is absorbed mainly in the small intestinal tract. Absorption is largely due to the galenic form of the drug - max up to 80% when taken on an empty stomach.
The substance binds to plasma proteins almost 100%. This is due to the fact that levothyroxine does not lend itself to hemoperfusion or hemodialysis. The period of his half-life is determined by the concentration of thyroid hormones in the patient's blood: in euthyroid states, its duration is 6-7 days, with thyrotoxicosis 3-4 days, with hypothyroidism 9-10 days).
About a third of the substance is accumulated in the liver. In this case, it quickly begins to interact with levothyroxine, which is in the blood plasma.
Splitting of levothyroxine is carried out mainly in muscle tissue, liver and brain tissue. Active lyotyronine, which is a product of the metabolism of the substance, is excreted in the urine and intestinal contents.

Indications for use

L-Thyroxine is used for maintenance of HRT with hypothyroid conditions of various origins, including primary and secondary hypothyroidism that developed after surgery on thyroid as well as conditions provoked by therapy with the use of radioactive iodine preparations.
It is also advisable to prescribe the drug:
    at a hypothyrosis (both at congenitality, and in a case when the pathology is a consequence of lesions of a hypothalamic-pituitary system);
    with obesity and / or cretinism, which are accompanied by manifestations of hypothyroidism;
    at cerebral-pituitary diseases;
    as a prophylactic for relapsing nodular goiter after thyroid resection (if its function is not changed);
    for the treatment of diffuse euthyroid goiter (L-Thyroxine is used as an independent agent);
    for the treatment of euthyroid hyperplasia of thyroid gland, as well as Graves' disease after attaining indemnification of thyroid hormone intoxication with the help of thyreostatics (as part of complex therapy);
    with Graves' disease and Hashimoto's disease (in complex treatment);
    for the treatment of patients with hormone-dependent differentiated malignant tumors in the thyroid gland (including papillary or follicular carcinoma);
    for suppressive therapy and HRT in patients with malignant tumors in the thyroid (including after surgery for thyroid cancer); as a diagnostic tool in conducting thyroid suppression tests.
In addition, thyroxine is often used in bodybuilding as a means of losing weight.

Contraindications

L-Thyroxine is contraindicated when:
    hypersensitivity to the drug;
    acute myocardial infarction;
    acute inflammatory lesions of the heart muscle;
    untreated thyrotoxicosis;
    untreated hypocorticism;
    hereditary galactosemia, lactase deficiency, the syndrome of impaired intestinal absorption.
With caution should be used in patients with heart and vascular disease (including including IHD, a history of myocardial infarction, angina pectoris, atherosclerosis, arrhythmia, arterial hypertension), long-term severe hypothyroidism, diabetes mellitus.
The presence in the patient of any of the above diseases is a prerequisite for changing the dose.

Side effects of L-Thyroxine

Proper use of the drug under the supervision of a doctor is not accompanied by side effects. In persons with hypersensitivity, treatment with levothyroxine may be accompanied by allergic reactions.
Other side effects are usually due to an overdose of L-Thyroxine. Very rarely, they can be triggered by taking the medication at the wrong dose, as well as by a too rapid increase in the dose (especially at the initial stages of treatment).
Side effects of L-Thyroxine are most often expressed as:
    feelings of anxiety, tremors, headaches, insomnia, pseudotumor brain;
    arrhythmias (including atrial fibrillation), tachycardia, angina pectoris, palpitation, extrasystole;
    vomiting and diarrhea;
    rashes on the skin, skin itching, angioedema;
    pathologies of the menstrual cycle;
    hyperhidrosis, hyperthermia, a feeling of heat, weight loss, increased weakness, muscle cramps.
The appearance of the above symptoms is the reason for reducing the dose of L-Thyroxine or stopping treatment with the drug for several days.
Cases of sudden death on the background of cardiac abnormalities in patients using levothyroxine in elevated doses for a long time were recorded.
After the disappearance of side effects, therapy is continued, with care choosing the optimal dose. When allergic reactions occur (bronchospasm, urticaria, laryngeal edema and - in some cases - anaphylactic shock), the drug is stopped.

L-Thyroxine: instructions for use

The daily dose of the drug is determined individually depending on the indications. Tablets are taken on an empty stomach with a small amount of liquid (not liquid), at least half an hour before meals.
Patients under 55 with a healthy heart and blood vessels during the substitution therapy are shown taking the drug at a dose of 1.6 to 1.8 μg / kg. Persons who are diagnosed with various heart / vascular diseases, as well as patients older than 55 years of age, are reduced to 0.9 μg / kg.
Persons whose body mass index exceeds the figure of 30 kg / m 2, the calculation is carried out, focusing on the "ideal weight".
At the initial stages of treatment for hypothyroidism, the dosing regimen for the various patient groups is as follows:
    75-100 mcg / day / 100-150 mcg / day. - respectively, for women and men, provided that their heart and vascular system function normally.
    25 mcg / day. - Persons over 55 years of age, as well as persons diagnosed with cardiovascular diseases. Two months later, the dose is raised to 50 mcg. Correct the dose, increasing it by 25 mcg every other 2 months, until the thyrotropin values ​​in the blood are normalized. In case of occurrence or aggravation of symptoms from the side of the heart or vessels, a change in the treatment regimen of heart disease / blood vessels is required.
In accordance with the instructions for the use of levothyroxine sodium, patients with congenital hypothyroidism dose should be calculated according to age.
For children from birth to half a year, the daily dose varies from 25 to 50 μg, which corresponds to 10-15 μg / kg / day. when recalculating to body weight. Children from half a year to a year are prescribed at 50-75 mcg / day, children from one to five years old - from 75 to 100 mcg / day, children over 6 years old - from 100 to 150 mcg / day, adolescents over 12 years old - from 100 to 200 μg / day.
The instructions for L-Thyroxine indicate that infants and children under 36 months of age should be given a single dose, half an hour before the first feeding. Immediately prior to taking the L-Thyroxine tablet, it is placed in water and dissolved until a fine suspension is formed.
With hypothyroidism, EL-Thyroxine is usually taken throughout life. In thyrotoxicosis, after the euthyroid state is achieved, sodium levothyroxin is prescribed in combination with antithyroid drugs. The duration of treatment in each case is determined by the doctor.

The scheme of taking L-Thyroxine for weight loss

In order to lose excess pounds, the drug starts taking 50 μg / day, dividing the indicated dose into 2 divided doses (both should be in the first half of the day).
Therapy is supplemented with the use of β-blockers, the dose of which is adjusted depending on the pulse rate.
In the future, the dose of levothyroxine is gradually increased to 150-300 mcg / day, dividing it into 3 doses until 18:00. In parallel with this, the daily dose of the β-adrenoblocker is increased. Select it is recommended individually, so that the heart rate at rest does not exceed 70 beats per minute, but at the same time was greater than 60 beats per minute.
The appearance of pronounced side effects is a prerequisite for reducing the dose of the drug.
The duration of the course is from 4 to 7 weeks. Stop taking medication smoothly, lowering the dose every 14 days until complete withdrawal.
If diarrhea occurs on the background of the application, the course is supplemented with the appointment of Loperamide, which takes 1 or 2 capsules per day.
Between the courses of taking levothyroxine should be maintained intervals of at least 3-4 weeks.

Overdose

Symptoms of overdose are:
    heart palpitations and pulse;
    increased anxiety;
    feeling of heat;
    hyperthermia;
    hyperhidrosis (increased sweating);
    insomnia;
    arrhythmia;
    increased frequency of angina attacks;
    weight loss;
    anxiety;
    tremor;
    diarrhea;
    vomiting;
    muscle weakness and cramps;
    pseudotumor brain;
    malfunctions of the menstrual cycle.
Treatment involves the withdrawal of L-Thyroxine and the conduct of follow-up examinations.
With the development of severe tachycardia to reduce its severity, the patient is prescribed β-adrenoblockers. Due to the fact that the thyroid function is completely suppressed, it is not advisable to use thyreostatic medications.
When taking levothyroxine in extreme doses (when attempting suicide) it is effective to conduct plasmapheresis.

Interaction

The use of levothyroxine reduces the effectiveness of antidiabetic drugs. At the beginning of treatment with the drug, and also every time after a dose change, it is more often necessary to monitor the level of glucose in the blood.
Levothyroxine potentiates the effects of anticoagulants (in particular, coumarinic series), thereby increasing the risk of cerebral hemorrhage (dorsal or head), as well as gastrointestinal bleeding (especially in the elderly).
Thus, if necessary to take these drugs in combination, it is recommended that a regular blood test for clotting be performed and, if appropriate, a reduction in the dose of anticoagulants.
The effect of levothyroxine may be impaired when taken concomitantly with protease inhibitors. In this regard, the concentration of thyroid hormones must be constantly monitored. In some situations, a dose review of L-Thyroxine may be required.
Kolestyramin and colestipol slow the absorption of levothyroxine, so L-Thyroxine should be taken no less than 4-5 hours before taking these drugs.
Preparations that contain aluminum, calcium carbonate or iron can reduce the effects of levothyroxine, so L-Thyroxine should be taken at least 2 hours prior to admission.
Absorption of levothyroxine decreases when taken in combination with lanthanum carbonate or sevelamer, so it should be taken one hour before or three hours after the application of these agents.
In the case of taking drugs in combination at the initial and final stages of their simultaneous application, it is necessary to control the level of thyroid hormones. You may need to change the dose of levothyroxine.
The efficacy of the agent is reduced by simultaneous administration with tyrosine kinase inhibitors, and therefore changes in thyroid function at the initial and concluding stages of simultaneous application of these drugs should be controlled.
Proguanil / chloroquine and sertraline reduce the effectiveness of the drug and provoke an increase in plasma concentrations of thyrotropin.
Drug-induced enzymes (eg, carbamazepine or barbiturates) can increase Clupec of levothyroxine.
Women taking hormonal contraceptives containing an estrogen component, as well as women taking hormone replacement drugs at postmenopausal age, may require an increase in the dose of levothyroxine.

Thyroxine and L-Thyroxine

Furosemide in increased dosage, salicylates, clofibrate and a number of other substances contribute to the displacement of levothyroxine from plasma proteins, which in turn provokes an increase in the fraction of fT4 (free thyroxine).
Iodine-containing drugs, GCS, Amiodarone, propylthiouracil, sympatholytics inhibit the peripheral transformation of thyroxin into triiodothyronine. Due to the high concentration of iodine, amiodarone may cause the patient to develop both hypo- and hyperthyroid conditions.
With special care, amiodarone is used in combination with L-Thyroxine for the treatment of patients with nodular goiter of the unspecified etiology.
Phenytoin promotes the displacement of levothyroxine from plasma proteins. As a consequence, the patient's level of fractions of free thyroxin and free triiodothyronine increases.
In addition, phenytoin stimulates the metabolic transformations of levothyroxine in the liver, therefore patients receiving levothyroxine in combination with phenytoin are recommended to monitor the concentration of thyroid hormones continuously.

Storage conditions

Store in a dry, light-shielded, out of reach of children place. The optimum storage temperature is up to 25 degrees Celsius.
Shelf life - The drug is suitable for use within 3 years after the release date.

special instructions

What is levothyroxine sodium? Wikipedia states that this remedy is the sodium salt of L-Thyroxine, which after partial biotransformation in the kidneys and liver affects the metabolic processes, as well as the growth and development of body tissues.
The gross formula of the substance is C15H11I4NO4.
In turn, thyroxine is an iodinated amino acid derivative of tyrosine, the main hormone of thyroid.
Being biologically inactive, the hormone thyroxin under the influence of a special enzyme undergoes conversion into a more active form - triiodothyronine, that is, inherently is a prohormone.
The main functions of the thyroid hormone are:
    stimulating the growth and differentiation of tissues, as well as increasing their oxygen demand;
    increased systemic BP, as well as the strength and frequency of contractions of the heart muscle;
    increasing the level of wakefulness;
    stimulation of mental activity, motor and mental activity;
    stimulation of the level of basal metabolism;
    increased blood glucose levels;
    increased gluconeogenesis in the liver;
    inhibition of glycogen production in skeletal muscles and liver;
    increasing the uptake and utilization of glucose by cells;
    stimulation of activity of the main enzymes of glycolysis;
    increased lipolysis;
    inhibition of fat formation and storage processes;
    increased sensitivity of tissues to catecholamines;
    strengthening erythropoiesis in the bone marrow;
    reduction of tubular reabsorption of water and hydrophilicity of tissues.
The use of thyroid hormones in small doses provokes an anabolic effect, in high doses it has a powerful catabolic effect on protein metabolism. In medicine, thyroxine is used to treat hypothyroid conditions.
Symptoms of thyroid deficiency are as follows:
    weakness, fatigue;
    impaired concentration of attention;
    unexplained weight gain;
    alopecia;
    dry skin;
    depression;
    increased cholesterol;
    malfunctions of the menstrual cycle;
    constipation.
To correctly choose the dose of the drug, patients with impaired thyroid function should undergo a doctor's examination and take blood tests, the main indicators of which are the concentration indices:
    thyrotropin;
    free triiodothyronine;
    free thyroxine;
    antibodies to thyroglobulin;
    microsomal antibodies (antibodies to thyroid peroxidase).
Norm of thyroxine in men - from 59 to 135 nmol / l, the norm of the hormone in women - from 71 to 142 nmol / l.
Free triiodthyronine ft3 and free thyroxine ft4 - what is it? Free triiodothyronine is a hormone that stimulates the exchange and utilization of oxygen by tissues. Free thyroxin stimulates the synthesis of proteins.
Reduction of the total thyroxine T4, as a rule, is observed after surgery for thyroidectomy, therapy with the use of preparations of radioactive iodine, treatment of thyroid hyperfunction, as well as against the background of the development of autoimmune thyroiditis.
The norm of free thyroxine t4 in women and men - 9.0-19.1 pmol / l, free triiodothyronine - 2.6-5.7 pmol / l. If the free thyroxine T4 is lowered, talk about the failure of thyroid function, that is, hypothyroidism.
If thyroxine free t4 is lowered, and the thyrotropin concentration index is within the normal range, there is a possibility that a blood test was performed incorrectly.

Combination with alcohol

Single intake of a small dose of alcohol is not too high strength, as a rule, does not provoke any negative consequences for the body, so the instructions to the drug do not categorically prohibit such a combination.
However, it is acceptable only for patients with healthy hearts and blood vessels.
Drinking alcohol against the background of L-Thyroxine treatment often provokes a number of unwanted reactions from the central nervous system and liver, which in turn can affect the effectiveness of treatment.

L-Thyroxine for weight loss

By its effectiveness, thyroxin significantly exceeds the majority of fat burning agents (including pharmacological). According to the instructions, it accelerates metabolism, increases calorie consumption, enhances heat production, stimulates the central nervous system, suppresses appetite, reduces the need for sleep and improves physical performance.
In this regard, there are many positive reviews about the use of levothyroxine sodium for weight loss. However, those who want to lose weight should remember that the drug increases the frequency of contractions of the heart muscle, causes feelings of anxiety and excitement, thus having a negative impact on the heart.
To prevent the development of side effects, experienced bodybuilders advise the use of eL-Thyroxine for weight loss in combination with antagonists (blockers) of β-adrenergic receptors. This allows you to normalize the heart rate and reduce the severity of some other side effects that accompany thyroxine.
The advantages of L-Thyroxine for weight loss are high efficiency and availability of this remedy, a disadvantage is a large number of side effects. Despite the fact that many of them can be eliminated or even prevented, before using the drug in order to lose excess pounds, it is recommended to consult with a specialist.

Application in pregnancy

Treatment with thyroid hormones should be carried out consistently, especially during periods of pregnancy and lactation. Despite the fact that L-Thyroxine during pregnancy is used widely enough, there is no precise data on its safety for the developing fetus.
The amount of thyroid hormones penetrating the breast milk (even if the therapy is administered with high doses of the drug) is insufficient to provoke a child of maternal age to oppress the secretion of thyrotropin or the development of thyrotoxicosis.

Reviews about L-Thyroxine

Reviews on L-Thyroxine are mainly positive. The drug normalizes the balance of hormones in the body, which in turn has a beneficial effect on overall well-being.
Nevertheless, in the general mass of good responses from EL-Thyroxine there are also negative, which are associated primarily with the side effects of the drug.
Reviews about levothyroxine sodium for weight loss suggest that the drug, although it causes a number of side effects, but the weight really helps to adjust (especially if its reception is supplemented with a low-carbohydrate diet).
In this case, it is important to remember that you can take the medicine only according to the doctor's prescription and only with reduced thyroid function. Excess weight is often one of the signs that the body is broken, so reducing fat deposits is a kind of side effect of therapy.
For people who have normal functioning of the body, taking levothyroxine can be dangerous.