CYTOMEL is an L-triiodothyronine (T3) indicated for:

• Hypothyroidism: As replacement in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism (1.1)
• Pituitary Thyroid-Stimulating Hormone (TSH) Suppression: As an adjunct to surgery and radioiodine therapy in the management of well-differentiated thyroid cancer (1.2)
• Thyroid Suppression Test: As a diagnostic agent in suppression tests to differentiate suspected mild hyperthyroidism or thyroid gland autonomy (1.3)

Limitations of Use:

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Not indicated for suppression of benign thyroid nodules and nontoxic diffuse goiter in iodine-sufficient patients. (1)

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Not indicated for treatment of hypothyroidism during the recovery phase of subacute thyroiditis. (1)

• Administer CYTOMEL orally once daily and individual dosage according to patient response and laboratory findings (2.1)
• See full prescribing information for recommended dosage for hypothyroidism (2.2) TSH suppression in well-differentiated thyroid cancer (2.3) and for thyroid suppression test (2.4)
• When switching a patient to CYTOMEL, discontinue levothyroxine therapy and initiate CYTOMEL at a low dosage. Gradually increase the dose according to the patient's response (2.5)
• Adequacy of therapy determined with periodic monitoring of TSH and T3 levels as well as clinical status (2.6)

Tablets: 5 mcg, 25 mcg, 50 mcg (3)

Uncorrected adrenal cortical insufficiency (4)

• Cardiac adverse reactions in the elderly and in patients with underlying cardiovascular disease: Initiate CYTOMEL at less than the full replacement dose because of the increased risk of cardiac adverse reactions, including atrial fibrillation (2.3, 5.1, 8.5)
• Myxedema coma: Do not use oral thyroid hormone drug products to treat myxedema coma. (5.2)
• Acute adrenal crisis in patients with concomitant adrenal insufficiency: Treat with replacement glucocorticoids prior to initiation of CYTOMEL treatment (5.3)
• Prevention of hyperthyroidism or incomplete treatment of hypothyroidism: Proper dose titration and careful monitoring is critical to prevent the persistence of hypothyroidism or the development of hyperthyroidism. (5.4)
• Worsening of diabetic control: Therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control after starting, changing, or discontinuing thyroid hormone therapy (5.5)
• Decreased bone mineral density associated with thyroid hormone over-replacement: Over-replacement can increase bone resorption and decrease bone mineral density. Give the lowest effective dose (5.6)

Most common adverse reactions for CYTOMEL are primarily those of hyperthyroidism due to therapeutic overdosage: arrhythmias, myocardial infarction, dyspnea, headache, nervousness, irritability, insomnia, tremors, muscle weakness, increased appetite, weight loss, diarrhea, heat intolerance, menstrual irregularities, and skin rash (6)

To report SUSPECTED ADVERSE REACTIONS, contact Pfizer, Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

See full prescribing information for drugs that affect thyroid hormone pharmacokinetics and metabolism (e.g., absorption, synthesis, secretion, catabolism, protein binding, and target tissue response) and may alter the therapeutic response to CYTOMEL (7)

Pregnancy may require the use of higher doses of thyroid hormone (2.2, 8.1)