Synthroid

Synthroid (Levothyroxine)

Synthroid is used at treatment of the reduced level of thyroid gland (hypothyroidism), for the prophylaxis and treatment of enlarged thyroid, which was caused by surgery, radial therapy, cancer or hormonal disbalance.

Administer Synthroid in accordance with prescriptions of your attending physician.
Take Synthroid in the morning upon a fasting stomach with a glass of water, in 30 minutes before eating.

Synthroid is a thyriod hormone substitude. Thyroid gland produces such hormone, which regulates energy and metabolism of a body. Synthroid is prescribed when there is insufficient level of the thyroid hormone in the organism.

Pharmacological action
Levorotatory isomer of thyroxine, after partial metabolism in the liver and kidneys influences the metabolism and development and growth of tissues. Binding of the receptor to the genome, oxidative metabolism changing in mitochondria, substrates flow regulation and regulation of cations outside and inside the cell are the mechanisms of metabolic effects. Synthroid (Levothyroxine) has an anabolic effect in small doses. In medium doses Synthroid (Levothyroxine) stimulates the development and growth of tissues, stimulates the metabolism of carbohydrates, fats and proteins, increases the need of tissues in oxygen, increases the functionality of the central nervous system and cardiovascular system. In high doses Synthroid (Levothyroxine) suppresses the production of thyrotropin-releasing hormone of the hypothalamus and pituitary thyroid-stimulating hormone. The therapeutic effect was observed after 7-12 days, during the same time retained after the drug effect. Clinical effect of hypothyroidism seen after 3-5 days. Basedows disease is reduced or disappears within 3-6 months, with the late stages of a significant reduction of nodal thyroid size observed in 30% of cases, but nearly all patients prevented its further growth.

Pharmacokinetics
Absorbed in the small intestine by 70-80% (in the fasting state). Food intake reduces absorption. TCmax - 6 hours. Relationship to plasma proteins - 99%. Metabolism occurs mainly in muscles, brain and liver in the form of levothyroxine mono- deiodination with the formation of triiodothyronine (T3), with more pronounced than that of thyroxine hormone action, and non-active products. A small amount of Synthroid drug undergoes decarboxylation and deamination, forming tetraiodthyroacetic acid and conjugation with glucuronic and sulfuric acids (in liver). T1 / 2 is approximately 6-8 days. About 15% of the drug excreted by the kidneys and bile in unchanged form and as conjugates.

If you missed planned dose of Synthroid - do it as it will be possible, follow prescription and dont take more than 1 dose at once in the case, when the intake of missed dose coincides with your regular.

Store Synthroid at temperature 20-25 C (68-77 F) in protected from light, moisture and high temperature place away from children and pets.

Synthroid is contraindicated if:
You are hypersensitive to Synthroid ingridients; You have or had stenocardia, a heart attack, increased thyroid hormone level, that has not been healed.
It is necessary to take Synthroid pills with a large amount of water because wrong intake can cause a pill stuck in throat Before any dental or surical procedures You have to warn your doctor or dentist that you take Synthroid. Synthroid can affect on sugar level in a blood at patients with diabetes, so it is necessary to consult with an attending physician according to the changes in the dosage of drugs for diabetes. Regular laboratory test are required during the therapy with Synthroid for monitoring of the process. Synthroid should be used with care at children, since it can reduce growth in adult age at increased dosage. During pregnancy and lactation physicians consultation according usage of Synthroid is required.

There can be several insignificant side effects when using Synthroid:

anxiety, indigestion, vomiting, mood changes, temporary hair loss, weakness in the muscles, insomnia, stomach spasms, increased fatigue.

If such symptoms are observed at you, immediately seek medical help:

Allergic reactions (swelling of the mouth, face, lips, tongue, itching, difficult breathing, rash, urticaria), changes in appetite, pain in the chest; increased perspiration, raised heart rate, headache, tachycardia, irritability, leg cramps , anxiety, tremors, breathlessness, increasing or losing of weight.

Synthroid is to be used only by the patient for whom it is prescribed. Do not share it with other people.
If your symptoms do not improve or if they become worse, check with your doctor.

Interaction
Reduces effects of oral hypoglycemic drugs and insulin, cardiac glycosides, increases - indirect anticoagulants (increased prothrombin time), tricyclic antidepressants. Cholestyramine, cholestypole, aluminum hydroxide reduce the plasma concentration due to inhibition of intestinal absorption. Phenytoine reduces the amount of levothyroxine-related protein, and the concentration of thyroxine (T4) by 15 and 25% respectively. Estrogens increase the concentration of thyroglobulin related to the fraction (efficiency decreases). While the use of anabolic steroids, asparaginase, clofibrate, furosemide, salicylates, tamoxifen pharmacokinetic interaction at the level of protein binding is possible. On the synthesis, secretion, distribution and metabolism of the drug is influenced by amiodarone, aminoglutethimide, PAS, ethionamide, beta-blockers, antithyroid drugs, chloral hydrate, carbamazepine, diazepam, L-DOPA, dopamine, metoclopramide, lovastatin, somatostatin. While the use of phenytoin, salicylates, high doses of furosemide, clofibrate increases the concentration of drug in the blood.