Liothyronine Sodium Tablets

(Commercial Product)

Available Dosage Strengths

5 mcg | 25 mcg | 50 mcg

Want to Prescribe?

Disclaimer: Images are for reference only; actual products may vary.

Product Overview

Description

Liothyronine is synthetically made to function similar as the endogenous thyroid hormone triiodothyronine. It comes as an oral tablet and is indicated for use as replacement or supplemental therapy in the treatment of hypothyroidism. There are two forms of thyroid in the human body thyroxine (T4) and triiodothyronine (T3). Triiodothyronine is more biologically active. T3 is faster-acting than T4 and can be used for patients who poorly convert T4 to T3.

Liothyronine is indicated for the treatment of

Hypothyroidism: As replacement in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism.
Pituitary Thyrotropin (Thyroid-Stimulating Hormone, TSH) Suppression: As an adjunct to surgery and radioiodine therapy in the management of well-differentiated thyroid cancer.
Thyroid Suppression Test: As a diagnostic agent in suppression tests to differentiate suspected mild hyperthyroidism or thyroid gland autonomy. [1,2]

Mechanism of Action

Triiodothyronine exerts its physiologic actions through control of DNA transcription and protein synthesis. It does this by entering into the cell nucleus and binding to thyroid receptor proteins attached to DNA. This hormone nuclear receptor complex activates gene transcription and synthesis of messenger RNA and cytoplasmic proteins. The physiological actions of thyroid hormones are produced predominantly by T3. [1]

Adverse Reactions

Common (mimic symptoms of hyperthyroidism)

Cardiac-arrhythmias, myocardial infarction, palpitations
Nervousness or anxiety
Irritability
Insomnia
Weight loss
Heat intolerance
Diarrhea or abdominal cramps

Temporary hair loss, especially in pediatric patients early in therapy. [1,2]

Contraindications & Precautions

Contraindications

Hypersensitivity to liothyronine or any tablet component.

Precautions

Use caution in patients with cardiovascular disease (e.g., angina, coronary artery disease, arrhythmias) due to the risk of exacerbation from increased metabolic demands.
Monitor glucose levels in diabetic patients; thyroid hormone can alter insulin requirements.
Use lower initial doses in elderly patients or those with longstanding hypothyroidism.
Osteoporosis risk increases with over-replacement of thyroid hormone. [1]

Storage

Store at 15°C to 30°C (59°F to 86°F). Protect from light and moisture. Keep in a tightly closed container. [1,2]

References

Cytomel (Liothyronine Sodium) Prescribing Information. FDA. www.accessdata.fda.gov/drugsatfda_docs/label/2018/010379s054lbl.pdf. Revised December 2018. Accessed May 26, 2025.
Clinical Pharmacology liothyronine clinical monograph 2025 https://www.clinicalkey.com/pharmacology/

Disclaimer

This sheet is a summary. It may not cover all possible drug information about this product. Call your doctor for medical advice and/or about side effects. You may report side effects to the FDA at 1-800-FDA-1088. A Wells Pharmacy Network pharmacist will be happy to answer any questions. For consultation, please call 1-800-622-4510.