TGP Levothyroxine Sodium Special Precautions

Levothyroxine sodium is contraindicated in untreated hyperthyroidism. It should be used with extreme caution in patients with cardiovascular disorders including angina, heart failure, myocardial infarction, and hypertension; lower initial doses, smaller increments, and longer intervals between increases should be used as necessary. An ECG performed before starting treatment with levothyroxine sodium may help to distinguish underlying myocardial ischaemia from changes induced by hypothyroidism. Levothyroxine sodium should also be introduced very gradually in elderly patients and those with long-standing hypothyroidism to avoid any sudden increase in metabolic demands. It should not be given to patients with adrenal insufficiency without adequate corticosteroid cover otherwise the thyroid replacement therapy might precipitate an acute adrenal crisis. Care is also required when levothyroxine sodium is given to patients with diabetes mellitus or diabetes insipidus.
Tests if thyroid functions are subject to alteration by a number of nonthyroidal clinical conditions and by a wide variety of drugs, some of which are mentioned under interactions.
Adrenocortical insufficiency precautions: Thyroid-hormone replacement without concomitant treatment with corticosteroids may precipitate acute adrenocortical insufficiency in patients with impaired adrenocortical function, including those with subclinical or unrecognized adrenocortical disease. Prompt diagnosis and replacement of corticosteroids can prevent the development of a potentially fatal crisis. It has been pointed out that a raised concentration of thyroid-stimulating-hormone alone may not necessarily imply hypothyroidism in patients with chronic adrenocortical insufficiency. Even confirmed hypothyroidism in these patients may not be permanent.