NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated July 13, 2026

Liothyronine

Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026

Liothyronine is a synthetic form of triiodothyronine (T3), the most metabolically active thyroid hormone. It has a faster onset and shorter duration than levothyroxine and is sometimes used in combination with T4, for T3-only therapy in select cases, or for short-term TSH suppression in thyroid cancer diagnostic protocols. It is not considered first-line treatment for hypothyroidism.

Evidence tier
Moderate
Indexed sources
10 2015–2025
Interactions
0
Category
Prescription
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Publication status

Exploratory record, not a reviewed medical publication.

See the editorial and medical-review policies for the publication gate.

This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.

In short

What the research says.

A quick, data-only summary. The full evidence, dosing, and sources are below.

Liothyronine is a synthetic form of triiodothyronine (T3), the most metabolically active thyroid hormone. NutriStack rates the supporting evidence as moderate. Common adult dosing is 5–75 mcg daily in divided doses; combination therapy typically 5–15 mcg daily (as prescribed by your physician), though a prescriber sets the actual dose. This profile indexes 10 sources.

What it's good for
  • Rapid onset of thyroid hormone action7,2
  • Useful when quick thyroid hormone replacement is needed7,2
  • May help patients who poorly convert T4 to T3
  • Used in thyroid cancer withdrawal protocols2,7
  • Can be added to T4 therapy in select non-responders
What to watch for
  • Tachycardia and palpitations
  • Tremor
  • Insomnia and nervousness
  • Untreated adrenal insufficiency
  • Acute myocardial infarction (unless hypothyroidism is contributory)

The bottom line

Evidence rating moderate. Most-documented uses: rapid onset of thyroid hormone action, useful when quick thyroid hormone replacement is needed, may help patients who poorly convert t4 to t3. 10 sources indexed (2015–2025), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

Synthetic T3 that directly binds nuclear thyroid hormone receptors without requiring peripheral conversion. Activates gene transcription for proteins involved in oxygen consumption, basal metabolic rate, carbohydrate and lipid metabolism, and thermogenesis. Its direct action explains the rapid onset compared to T4-based therapies.7,2

Class
Thyroid Hormone
Absorption
Best on an empty stomach
Dosing

Dosing & protocol.

Common range
5–75 mcg daily in divided doses; combination therapy typically 5–15 mcg daily (as prescribed by your physician)
Recommended form
Oral tablet; IV formulation (Triostat) for myxedema coma

Take on an empty stomach, ideally 30–60 minutes before food. Often dosed in divided doses (BID or TID) due to short half-life.

Safety

Full safety detail.

Side effects

  • Tachycardia and palpitations
  • Tremor
  • Insomnia and nervousness
  • Heat intolerance and sweating
  • Weight loss
  • Diarrhea
  • Angina (in patients with coronary artery disease)
  • Arrhythmias

Contraindications

  • Untreated adrenal insufficiency
  • Acute myocardial infarction (unless hypothyroidism is contributory)
  • Uncorrected thyrotoxicosis
  • Known hypersensitivity to liothyronine1,2
Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Meta-analyses & systematic reviews

4

Randomized controlled trials

2

Reference material

4
FAQ

Common questions.

Quick answers about Liothyronine, drawn from the data on this page.

What is Liothyronine?

Liothyronine is a synthetic form of triiodothyronine (T3), the most metabolically active thyroid hormone. It has a faster onset and shorter duration than levothyroxine and is sometimes used in combination with T4, for T3-only therapy in select cases, or for short-term TSH suppression in thyroid cancer diagnostic protocols. It is not considered first-line treatment for hypothyroidism.

What is Liothyronine used for?

Commonly cited benefits of Liothyronine include: Rapid onset of thyroid hormone action; Useful when quick thyroid hormone replacement is needed; May help patients who poorly convert T4 to T3; Used in thyroid cancer withdrawal protocols; Can be added to T4 therapy in select non-responders. NutriStack rates the overall evidence as moderate.

What is a typical dose of Liothyronine?

A typical adult dose of Liothyronine is 5–75 mcg daily in divided doses; combination therapy typically 5–15 mcg daily (as prescribed by your physician). The commonly recommended form is Oral tablet; IV formulation (Triostat) for myxedema coma. These are general ranges, not personalized advice; confirm the right dose with a clinician.

What are the side effects of Liothyronine?

Reported side effects include tachycardia and palpitations, tremor, insomnia and nervousness, heat intolerance and sweating, weight loss, diarrhea. This is educational information; check with a healthcare professional before use.

How strong is the evidence for Liothyronine?

NutriStack rates this as Moderate, meaning several aligned RCTs or one large RCT plus supporting reviews. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.

Use this with your stack

Liothyronine in NutriStack.

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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.