levothyroxine sodium




Zuellig Pharma
Concise Prescribing Info
Levothyroxine Na
Dosage/Direction for Use
Adult Initially 50-100 mcg daily, adjust by 50 mcg at 4-6 wk intervals. Patient >50 yr Not to exceed 50 mcg daily, cardiac disease 50 mcg on alternate days, may be increased by 50 mcg on alternate days at approx 4 wk intervals. Congenital hypothyroidism Infant Initially 50 mcg on alternate days, may be increased by 50 mcg on alternate days at 2-4 wk intervals. Juvenile myxoedema Childn >1 yr Initially 2.5-5 mcg daily
Should be taken on an empty stomach: Take 30 min before meals.
Hypersensitivity. Thyrotoxicosis; Acute MI, myocarditis & pancarditis.
Special Precautions
Not to be used for obesity or wt loss. Cardiac symptoms, DM or diabetes insipidus; panhypopituitarism or other causes predisposing to adrenal insufficiency; myxoedema; malabsorption syndromes. Long-term & high-dose use. Pregnancy & lactation. Elderly.
Drug Interactions
Decreased absorption w/ cholestyramine, Ca-, Al-, Mg- & Fe supplements, polystyrene sulfonates, sucralfate, lanthanum, bile acid sequestrants (eg, colestipol), anion/cation exchange resins (eg, kayexalate, sevelamer), proton-pump inhibitors; wt loss drugs eg, orlistat. Decreased intestinal absorption w/ soy-containing compds, high-fibre diets. Enhanced metabolism w/ anticonvulsants eg, carbamazepine, phenytoin. Increased metabolism w/ enzyme inducers ie, rifampicin, barbiturates. Lowered therapeutic effect by propranolol, amiodarone, lithium, iodide, oral contrast agents, propylthiouracil, glucocorticoids. Increased dosage requirements in hypothyroid patients w/ tyrosine kinase inhibitors eg, imatinib, sunitinib. Reduced serum levels w/ sertraline. Increased dosage requirements w/ OCs, tamoxifene, clofibrate, methadone, 5-fluorouracil. Increased thyroid hormone requirements w/ HMG-CoA reductase inhibitors eg, simvastatin, lovastatin. Increased need for insulin or oral antidiabetics in patients w/ diabetes. Increased effect of anticoagulants. Increased phenytoin levels. Increased receptor sensitivity to catecholamines. Accelerated response to TCAs. Enhanced effects of sympathomimetic agents. Potential interaction w/ ritonavir-containing products. Decreased dosage requirements w/ androgens, anabolic steroids. False low plasma conc w/ anti-inflammatory treatment eg, phenylbutazone or acetylsalicylic acid.
MIMS Class
ATC Classification
H03AA01 - levothyroxine sodium ; Belongs to the class of thyroid hormones.
Oroxine tab 100 mcg
100's (RM74.4/pack)
Oroxine tab 50 mcg
100's (RM59.75/pack)
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