Liotrix
- Atc Codes:H03AA03
- CAS Codes:8065-29-0
- PHARMGKB ID:8065-29-0
Table of contents
- Brand Names
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Caution and personalized dose adjustment in patients with the following genotypes
- Other genes that may be involved
- Substrate of
- Drug Interactions
- Dosage
- Pharmacokinetics and Pharmacodynamics
- Special Considerations
Brand Names
North America
USA: Thyrolar.
Drug combinations
Chemistry
Liotrix: A mixture of liothyronine sodium (C~15~H~11~I~3~NNaO~4~) and levothyroxine sodium (C~15~H~10~I~4~NNaO~4~ xH~2~O), in a ratio of 1:1 in terms of biological activity, or in a ratio of 1:4 in terms of weight. (1) L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salt, hydrate, mixt. with O-(4-hydroxy-3-iodophenyl)-3,5-diiodo-L-tyrosine monosodium salt; (2) Monosodium L-thyroxine hydrate mixt. with monosodium L-3-[4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl]alanine. CAS-8065-29-0 (1969).
Pharmacologic Category
Thyroid Agents. (ATC-Code: H03AA03).
Mechanism of action
Uniform mixture of synthetic T~4~ and T~3~ in 4:1 ratio. Thyroid hormone is believed to exert its many metabolic effects through control of DNA transcription and protein synthesis. Involved in normal metabolism, growth, and development. Promotes gluconeogenesis, increases utilization and mobilization of glycogen stores and stimulates protein synthesis, increases basal metabolic rate.
Therapeutic use
Replacement or supplemental therapy in hypothyroidism (uniform mixture of T~4~:T~3~ in 4:1 ratio by weight).
Pregnancy and lactiation implications
Untreated hypothyroidism may have adverse effects on fetal growth and development, and is associated with higher rate of complications. Treatment should not be discontinued during pregnancy.
Unlabeled use
Contraindications
Hypersensitivity to liotrix or any component of the formulation. Recent MI or thyrotoxicosis, uncomplicated by hypothyroidism. Uncorrected adrenal insufficiency, hypersensitivity to active or extraneous constituents.
Warnings and precautions
Use with caution in adrenal insufficiency, diabetes mellitus and insipidus, in myxedema (symptoms may be exaggerated or aggravated), in angina pectoris or other cardiovascular disease; also in the elderly. Thyroid supplements ineffective and potentially toxic for weight reduction. High doses may produce serious or even life-threatening toxic effects, particularly when used with some anorectic drugs.