EUTROXSIG

What it is

EUTROXSIG contains levothyroxine sodium 50, 75, 100 or 200 micrograms as the active ingredient. The tablets are white, biconvex, and round. Levothyroxine sodium is the monosodium salt of the levo isomer of thyroxine, the principal secretion of the thyroid gland.

Approved indications

— Management of demonstrated thyroid hormone deficiency. — Suppression of thyrotropin (TSH) for the management of TSH-responsive tumours of the thyroid.

Dosing overview

EUTROXSIG is best taken as a single daily dose first thing in the morning with water on an empty stomach, at least 30 minutes and preferably 60 minutes before the intake of any food or other medications. The dose should be individualised on the basis of clinical response and biochemical tests. Adults commence with thyroxine 50 to 100 micrograms daily, with the daily dose increased by 25 to 50 micrograms according to response at not less than 4-weekly intervals, up to 100 to 200 micrograms daily. In patients aged 60 years and over and in those with ischaemic heart disease, thyroxine therapy should normally be initiated with low doses (25 or 50 µg/day). Maintenance dose for adults is 100 to 200 µg per day.

Key safety warnings

Extreme caution is required in patients with a cardiovascular disorder, and in the event of cardiovascular effects, the dosage of EUTROXSIG should be lowered. Corticosteroid replacement therapy must precede initiation of EUTROXSIG therapy to avoid Addisonian crisis in such conditions as hypopituitarism and adrenal insufficiency. In women, long-term levothyroxine sodium therapy has been associated with increased bone resorption, thereby decreasing bone mineral density, especially in post-menopausal women on greater than replacement doses or in women who are receiving suppressive doses of levothyroxine sodium. It is recommended that patients receiving levothyroxine sodium be given the minimum dose necessary to achieve the desired clinical and biochemical response. When EUTROXSIG is given to hypothyroid patients with diabetes mellitus or diabetes insipidus, it may cause the required dosage of insulin and oral antidiabetic agents to be increased, and careful monitoring of diabetic control is recommended, especially when EUTROXSIG therapy is initiated, changed or discontinued. Levothyroxine should not be used for the treatment of obesity or weight loss. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for anorectic effects.

Contraindications

EUTROXSIG is contraindicated in known hypersensitivity to thyroxine, untreated hyperthyroidism, uncorrected primary or secondary adrenal insufficiency, thyrotoxicosis, acute myocardial infarction uncomplicated by hypothyroidism, acute myocarditis, and acute pancarditis. During pregnancy, combination of levothyroxine and antithyroid agents for the treatment of hyperthyroidism is contraindicated.

PBS listing

EUTROXSIG is listed on the PBS in four strengths: 50 micrograms (ex-manufacturer price A$8.03), 75 micrograms (A$8.17), 100 micrograms (A$8.32), and 200 micrograms (A$9.76). All strengths are restricted PBS items, with one PBS item per strength.

Regulatory history

EUTROXSIG levothyroxine sodium 50, 100 and 200 microgram tablets in bottle form were first listed on the ARTG on 28 August 2002. The 50, 100 and 200 microgram tablet blister packs were first listed on 17 May 2006. The 75 microgram tablet form in both bottle and blister pack was first listed on 5 February 2008.