Euthyrox®
The use of tricyclic antidepressants with levothyroxine sodium may lead to increased effects of the antidepressants.
Levothyroxine sodium reduces the effect of cardiac glycosides.
With simultaneous use of cholestyramine and colestipol (ion exchange resins), as well as aluminum hydroxide, they reduce the plasma concentration of levothyroxine sodium by inhibiting its absorption in the intestine. In this regard, levothyroxine sodium must be used 4-5 hours before taking these drugs.
When used simultaneously with anabolic steroids, asparaginase, tamoxifen, pharmacokinetic interaction is possible at the level of binding to plasma proteins.
Protease inhibitors (eg, ritonavir, indinavir, lopinavir) may affect the effectiveness of levothyroxine sodium. Close monitoring of thyroid hormone concentrations is recommended. If necessary, the dose of levothyroxine sodium should be adjusted. Phenytoin may affect the effectiveness of levothyroxine sodium due to the displacement of levothyroxine sodium from plasma proteins, which can lead to increased concentrations of free T4 and T3. On the other hand, phenytoin increases the rate of metabolism of levothyroxine sodium in the liver. Close monitoring of thyroid hormone concentrations is recommended.
Levothyroxine sodium may reduce the effectiveness of hypoglycemic drugs. Therefore, frequent monitoring of blood glucose concentrations is necessary from the start of thyroid hormone replacement therapy. If necessary, the dose of the hypoglycemic drug should be adjusted.
Levothyroxine sodium may enhance the effect of anticoagulants (coumarin derivatives) by displacing them from plasma proteins, which may increase the risk of bleeding, such as hemorrhage in the central nervous system or gastrointestinal bleeding, especially in elderly patients. Therefore, regular monitoring of coagulation parameters is necessary both at the beginning and during combination therapy with these drugs. If necessary, the dose of the anticoagulant should be adjusted. Salicylates, dicumarol, furosemide in high doses (250 mg), clofibrate and other drugs can displace levothyroxine sodium from binding to plasma proteins, which leads to an increase in the concentration of the free T4 fraction.
Orlistat: When orlistat is taken concomitantly with levothyroxine sodium, hypothyroidism may develop and/or decreased control of hypothyroidism may occur. The reason for this may be decreased absorption of iodine salts and/or levothyroxine sodium.
Sevelamer may reduce the absorption of levothyroxine sodium. Tyrosine kinase inhibitors (eg, imatinib, sunitinib) may reduce the effectiveness of levothyroxine sodium. Therefore, at the beginning or at the end of a course of concomitant therapy with these drugs, it is recommended to monitor changes in thyroid function in patients. If necessary, the dose of levothyroxine sodium is adjusted. Aluminum-containing drugs (antacids, sucralfate), iron-containing drugs, calcium carbonate are described in the literature as potentially reducing the effectiveness of levothyroxine sodium. Therefore, it is recommended to take levothyroxine sodium at least 2 hours before using such medications.
Somatropin, when used simultaneously with levothyroxine sodium, can accelerate the closure of epiphyseal growth plates.
Propylthiouracil, glucocorticosteroids, beta-sympatholytics, iodinated contrast agents and amiodarone inhibit the peripheral conversion of T4 to T3. Due to the high iodine content, the use of amiodarone may be accompanied by the development of both hyperthyroidism and hypothyroidism. Particular attention should be paid to nodular goiter with the possible development of unrecognized functional autonomy.
Sertraline, chloroquine/proguanil reduce the effectiveness of levothyroxine sodium and increase serum TSH concentrations. Drugs that induce hepatic enzymes (eg, barbiturates, carbamazepine) may enhance the hepatic clearance of levothyroxine sodium.
In women using estrogen-containing contraceptives or in postmenopausal women receiving hormone replacement therapy, the need for levothyroxine sodium may be increased.
Consumption of soy-containing products may reduce the intestinal absorption of levothyroxine sodium. Therefore, dosage adjustments may be necessary, especially when starting or stopping consumption of soy-containing products.
EUTIROX TAB 25MCG N100
The use of tricyclic antidepressants with levothyroxine sodium may lead to increased effects of the antidepressants.
Levothyroxine sodium reduces the effect of cardiac glycosides.
With simultaneous use of cholestyramine and colestipol (ion exchange resins), as well as aluminum hydroxide, they reduce the plasma concentration of levothyroxine sodium by inhibiting its absorption in the intestine. In this regard, levothyroxine sodium should be used 4–5 hours before taking these drugs.
When used simultaneously with anabolic steroids, asparaginase, tamoxifen, pharmacokinetic interaction is possible at the level of binding to plasma proteins.
Protease inhibitors (eg, ritonavir, indinavir, lopinavir) may affect the effectiveness of levothyroxine sodium. Close monitoring of thyroid hormone concentrations is recommended. If necessary, the dose of levothyroxine sodium should be adjusted. Phenytoin may affect the effectiveness of levothyroxine sodium due to the displacement of levothyroxine sodium from plasma proteins, which can lead to increased concentrations of free T4 and T3. On the other hand, phenytoin increases the rate of metabolism of levothyroxine sodium in the liver. Close monitoring of thyroid hormone concentrations is recommended.
Levothyroxine sodium may reduce the effectiveness of hypoglycemic drugs. Therefore, frequent monitoring of blood glucose concentrations is necessary from the start of thyroid hormone replacement therapy. If necessary, the dose of the hypoglycemic drug should be adjusted.
Levothyroxine sodium may enhance the effect of anticoagulants (coumarin derivatives) by displacing them from plasma proteins, which may increase the risk of bleeding, such as hemorrhage in the central nervous system or gastrointestinal bleeding, especially in elderly patients. Therefore, regular monitoring of coagulation parameters is necessary both at the beginning and during combination therapy with these drugs. If necessary, the dose of the anticoagulant should be adjusted. Salicylates, dicumarol, furosemide in high doses (250 mg), clofibrate and other drugs can displace levothyroxine sodium from binding to plasma proteins, which leads to an increase in the concentration of the free T4 fraction.
Orlistat: When orlistat is taken concomitantly with levothyroxine sodium, hypothyroidism may develop and/or decreased control of hypothyroidism may occur. The reason for this may be decreased absorption of iodine salts and/or levothyroxine sodium.
Sevelamer may reduce the absorption of levothyroxine sodium. Tyrosine kinase inhibitors (eg, imatinib, sunitinib) may reduce the effectiveness of levothyroxine sodium. Therefore, at the beginning or at the end of a course of concomitant therapy with these drugs, it is recommended to monitor changes in thyroid function in patients. If necessary, the dose of levothyroxine sodium is adjusted.
Medicines containing aluminum, iron and calcium salts: Aluminum-containing medicines (antacids, sucralfate) are described in the literature as potentially reducing the effectiveness of levothyroxine sodium. Therefore, it is recommended to take levothyroxine sodium at least 2 hours before using aluminum-containing medications. This recommendation applies to the use of medications containing iron and calcium salts.
Somatropin, when used simultaneously with levothyroxine sodium, can accelerate the closure of epiphyseal growth plates.
Propylthiouracil, glucocorticosteroids, beta-sympatholytics, iodinated contrast agents, and amiodarone inhibit the peripheral conversion of T4 to T3. Due to the high iodine content, the use of amiodarone may be accompanied by the development of both hyperthyroidism and hypothyroidism. Particular attention should be paid to nodular goiter with the possible development of unrecognized functional autonomy.
Sertraline, chloroquine/proguanil reduce the effectiveness of levothyroxine sodium and increase serum TSH concentrations.
Drugs that induce hepatic enzymes (eg, barbiturates, carbamazepine) may enhance the hepatic clearance of levothyroxine sodium.
In women using estrogen-containing contraceptives or in postmenopausal women receiving hormone replacement therapy, the need for levothyroxine sodium may be increased.
Consumption of soy-containing products may reduce the intestinal absorption of levothyroxine sodium. Therefore, dosage adjustments may be necessary, especially when starting or stopping consumption of soy-containing products.
EUTIROX TAB 75MCG N100
The use of tricyclic antidepressants with levothyroxine sodium may lead to increased effects of the antidepressants.
Levothyroxine sodium reduces the effect of cardiac glycosides.
With simultaneous use of cholestyramine and colestipol (ion exchange resins), as well as aluminum hydroxide, they reduce the plasma concentration of levothyroxine sodium by inhibiting its absorption in the intestine. In this regard, levothyroxine sodium should be used 4–5 hours before taking these drugs.
When used simultaneously with anabolic steroids, asparaginase, tamoxifen, pharmacokinetic interaction is possible at the level of binding to plasma proteins.
Protease inhibitors (eg, ritonavir, indinavir, lopinavir) may affect the effectiveness of levothyroxine sodium. Close monitoring of thyroid hormone concentrations is recommended. If necessary, the dose of levothyroxine sodium should be adjusted. Phenytoin may affect the effectiveness of levothyroxine sodium due to the displacement of levothyroxine sodium from plasma proteins, which can lead to increased concentrations of free T4 and T3. On the other hand, phenytoin increases the rate of metabolism of levothyroxine sodium in the liver. Close monitoring of thyroid hormone concentrations is recommended.
Levothyroxine sodium may reduce the effectiveness of hypoglycemic drugs. Therefore, frequent monitoring of blood glucose concentrations is necessary from the start of thyroid hormone replacement therapy. If necessary, the dose of the hypoglycemic drug should be adjusted.
Levothyroxine sodium may enhance the effect of anticoagulants (coumarin derivatives) by displacing them from plasma proteins, which may increase the risk of bleeding, such as hemorrhage in the central nervous system or gastrointestinal bleeding, especially in elderly patients. Therefore, regular monitoring of coagulation parameters is necessary both at the beginning and during combination therapy with these drugs. If necessary, the dose of the anticoagulant should be adjusted. Salicylates, dicumarol, furosemide in high doses (250 mg), clofibrate and other drugs can displace levothyroxine sodium from binding to plasma proteins, which leads to an increase in the concentration of the free T4 fraction.
Orlistat: When orlistat is taken concomitantly with levothyroxine sodium, hypothyroidism may develop and/or decreased control of hypothyroidism may occur. The reason for this may be decreased absorption of iodine salts and/or levothyroxine sodium.
Sevelamer may reduce the absorption of levothyroxine sodium. Tyrosine kinase inhibitors (eg, imatinib, sunitinib) may reduce the effectiveness of levothyroxine sodium. Therefore, at the beginning or at the end of a course of concomitant therapy with these drugs, it is recommended to monitor changes in thyroid function in patients. If necessary, the dose of levothyroxine sodium is adjusted.
Medicines containing aluminum, iron and calcium salts: Aluminum-containing medicines (antacids, sucralfate) are described in the literature as potentially reducing the effectiveness of levothyroxine sodium. Therefore, it is recommended to take levothyroxine sodium at least 2 hours before using aluminum-containing medications. This recommendation applies to the use of medications containing iron and calcium salts.
Somatropin, when used simultaneously with levothyroxine sodium, can accelerate the closure of epiphyseal growth plates.
Propylthiouracil, glucocorticosteroids, beta-sympatholytics, iodinated contrast agents, and amiodarone inhibit the peripheral conversion of T4 to T3. Due to the high iodine content, the use of amiodarone may be accompanied by the development of both hyperthyroidism and hypothyroidism. Particular attention should be paid to nodular goiter with the possible development of unrecognized functional autonomy.
Sertraline, chloroquine/proguanil reduce the effectiveness of levothyroxine sodium and increase serum TSH concentrations.
Drugs that induce hepatic enzymes (eg, barbiturates, carbamazepine) may enhance the hepatic clearance of levothyroxine sodium.
In women using estrogen-containing contraceptives or in postmenopausal women receiving hormone replacement therapy, the need for levothyroxine sodium may be increased.
Consumption of soy-containing products may reduce the intestinal absorption of levothyroxine sodium. Therefore, dosage adjustments may be necessary, especially when starting or stopping consumption of soy-containing products.
