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Liotrix

    Brands

    DEA Class; Rx

    Common Brand Names; Thyrolar

    • Thyroid Products

    Oral mixture of 2 synthetic thyroid hormones: T4 (levothyroxine) and T3 (liothyronine), in a 4-to-1 ratio by weight, respectively
    Used for hypothyroidism of almost any etiology, including congenital hypothyroidism (cretinism) and myxedema in adults and pediatric patients
    Levothyroxine is the preferred replacement therapy for routine use; combination of T3 an T4 therapy may be useful in select patients, such as those with symptoms despite stabilization of a dose for T4 replacement
    A “Liotrix-1” synthetic tablet is roughly comparable to a porcine thyroid USP 1 grain (60 mg) tablet (e.g., Armour Thyroid)

    For the treatment of hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis. This category includes cretinism (congenital hypothyroidism), myxedema, and ordinary hypothyroidism in patients of any age (pediatrics, adults, the elderly), or state (including pregnancy); primary hypothyroidism resulting from functional deficiency, primary atrophy, partial or total absence of thyroid gland, or the effects of surgery, radiation, or drugs with or without the presence of goiter; and secondary (pituitary), or tertiary (hypothalamic) hypothyroidism.
    For thyroid suppression testing as an aid for hyperthyroidism diagnosis in patients with signs of mild hyperthyroidism in whom baseline laboratory tests appear normal, or to demonstrate thyroid gland autonomy in patients with Grave’s ophthalmology.

    Hypersensitivity to thyroid hormone

    Acute MI uncomplicated by hypothyroidism, untreated thyrotoxicosis, untreated adrenal insufficiency

    Treatment of obesity

    Arrhythmias

    Increased blood pressure

    Chest pain

    Palpitation

    Anxiety

    Headache

    Urticaria

    Changes in menstrual cycle

    Insomnia

    Hyperhydrosis pruritus

    Tachycardia

    Nervousness

    Tremor

    Cramps

    Increased appetite

    Weight loss

    Diarrhea

    Caution in angina, cardiovascular disease, HTN, endocrine disorders, elderly

    Use caution in patients with adrenal insufficiency (symptoms may become exagerated or aggravated)

    Euthroid withdrawn from U.S. market

    Use caution in patients with myxedema (symptoms may become exagerated or aggravated)

    No advantage over levothyroxine & may do more harm (T3 overdosage) than good

    Not for the treatment of female infertility in euthyroid patients

    Pregnancy Category: A

    Lactation: Small amount excreted into breast milk, use caution

    Liotrix has a narrow therapeutic index; dosage must be individualized.

    Adults

    Doses greater than Thyrolar-2 (100 mcg T4 and 25 mcg T3)/day PO rarely needed.

    Elderly

    Doses greater than Thyrolar-2 (100 mcg T4 and 25 mcg T3)/day PO rarely needed.

    Adolescents

    Adolescents in whom growth and puberty are complete: Doses greater than Thyrolar-2 (100 mcg T4 and 25 mcg T3)/day PO rarely needed.

    Children

    Individualize dosage.

    Liotrix T3;T4

    Each 60 mg tablet will replace approximately 60-65 mg (1 grain) of desicated thyroid

    Liothyronine sodium (T3) is approximately 4 times as potent as levothyroxine (T4)

    tablet, T3/T4

    • Thyrolar 1/4 (15mg): 3.1/12.5mcg
    • Thyrolar 1/2 (30mg): 6.25/25mcg
    • Thyrolar 1 (60mg): 12.5/50mcg
    • Thyrolar 2 (120mg): 25/100mcg
    • Thyrolar 3 (180mg): 37.5/150mcg