levothyroxine sodium




Zuellig Pharma
Concise Prescribing Info
Levothyroxine Na
Benign euthyroid goitre. Prophylaxis of relapse after surgery for euthyroid goitre. Substitution therapy in hypothyroidism. Suppression therapy in thyroid cancer. Concomitant supplementation during antithyroid drug treatment of hyperthyroidism. 100 mcg: Diagnostic thyroid suppression testing.
Dosage/Direction for Use
Benign euthyroid goitre & prophylaxis of relapse after surgery for euthyroid goitre 75-200 mcg daily. Substitution therapy in hypothyroidism Adult Initially: 25-50 mcg daily. Maintenance: 100-200 mcg daily. Childn Initially: 12.5-50 mcg daily. Maintenance: 100-150 mcg/m2 daily. Concomitant supplementation during antithyroid drug treatment of hyperthyroidism 50-100 mcg daily. Suppression therapy in thyroid cancer 150-300 mcg daily. Diagnostic use for thyroid suppression testing, wk 2 & wk 1 prior test 200 mcg daily. Duration of treatment: Benign euthyroid goitre 6 mth up to 2 yr.
Should be taken on an empty stomach: Take 30 min before breakfast. Daily doses can be given in a single administration. For infants, tab is to be disintegrated in some water & the resultant susp given w/ some more liqd. Susp must be freshly prepared.
Hypersensitivity. Untreated adrenal & pituitary insufficiency, untreated thyrotoxicosis. Not to be initiated in acute MI, myocarditis & pancarditis. Combination therapy w/ antithyroid agent during pregnancy.
Special Precautions
Not to be given in hyperthyreotic states nor for wt reduction. Secondary hypothyroidism; CHD; severe or long-existing hypothyroidism. Coronary failure, angina pectoris, arteriosclerosis, HTN, pituitary, adrenal & cardiac insufficiency, tachycardiac arrhythmias; thyroid autonomy. Monitor patients at risk of psychotic disorders. Regularly check thyroid function. Diabetics & patients under anticoagulant therapy. Co-administration w/ orlistat. Postmenopausal women w/ increased risk of osteoporosis. Pregnancy & lactation. Monitor haemodynamic parameters in therapy of very low birth wt preterm neonates. Elderly.
Adverse Reactions
Tachycardia, palpitations, cardiac arrhythmias, anginal conditions, cephalalgia, muscular weakness & cramps, flushing, fever, vomiting, menstrual disorders, pseudotumor cerebri, tremor, restlessness, insomnia, hyperhidrosis, wt loss, diarrhoea. Hypersensitivity.
Drug Interactions
Reduced antidiabetic effects. Intensified coumarin derivative effects. Effects influenced by PIs eg, ritonavir, indinavir, lopinavir; phenytoin. Inhibited absorption w/ ion exchange resins eg, cholestyramine, colestipol. Decreased effect w/ Al-, Fe- & Ca-containing drugs. Elevated FT4 fraction w/ salicylates, dicumarol, high-dose furosemide (250 mg), clofibrate. Hypothyroidism &/or reduced control of hypothyroidism w/ orlistat. Decreased absorption w/ sevelamer. Decreased efficacy by tyrosine kinase inhibitors eg, imatinib, sunitinib; sertraline, chloroquine/proguanil. Inhibited peripheral T4-T3 conversion w/ propylthiouracil, glucocorticoids, β-sympatholytics, amiodarone, iodine-containing contrast media. Increased hepatic clearance by barbiturates or carbamazepine. Increased need of levothyroxine in women using oestrogen-containing contraceptives or post-menopausal women under hormone-replacement therapy. Decreased intestinal absorption w/ soy-containing compd.
MIMS Class
ATC Classification
H03AA01 - levothyroxine sodium ; Belongs to the class of thyroid hormones.
Euthyrox tab 100 mcg
Euthyrox tab 25 mcg
Euthyrox tab 50 mcg
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