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L-thyroxin
L-thyroxine is a synthetic thyroid hormone that replaces or supplements endogenous thyroid hormone to restore normal metabolic function.
L-thyroxine is a synthetic thyroid hormone that replaces or supplements endogenous thyroid hormone to restore normal metabolic function. Used for Hypothyroidism, Thyroid hormone replacement after thyroidectomy or radioactive iodine therapy, Thyroid cancer suppression therapy.
At a glance
| Generic name | L-thyroxin |
|---|---|
| Also known as | Euthyrox (Merck) |
| Sponsor | University of Tartu |
| Drug class | Thyroid hormone replacement |
| Target | Thyroid hormone receptors (TR-alpha, TR-beta) |
| Modality | Small molecule |
| Therapeutic area | Endocrinology |
| Phase | FDA-approved |
Mechanism of action
L-thyroxine (levothyroxine) is converted peripherally to the more active L-triiodothyronine (T3) and acts as a thyroid hormone replacement therapy. It binds to thyroid hormone receptors in target tissues to regulate metabolism, growth, and development. This restores normal thyroid hormone levels in patients with hypothyroidism or thyroid hormone deficiency.
Approved indications
- Hypothyroidism
- Thyroid hormone replacement after thyroidectomy or radioactive iodine therapy
- Thyroid cancer suppression therapy
Common side effects
- Tachycardia
- Tremor
- Anxiety
- Insomnia
- Heat intolerance
- Weight loss
Key clinical trials
- T4/T3 Therapy in Hypothyroidism (PHASE2)
- Dosing of LT4 in Older Individuals (PHASE4)
- Thyroid Hormone Replacement After Radio Iodine: Value and Efficacy
- Levothyroxine Treatment on Cardiac Function in Children With Subclinical Hypothyroidism (NA)
- COACH - Comparing Two Different Methods to Suppress Thyrotropin in Patients With Advanced Thyroid Cancer (PHASE2)
- Liothyronine in Combination With BIT Regimen for Medulloblastoma With or Without Minimal Residual Disease (PHASE1, PHASE2)
- Levothyroxine Treatment and IVF Outcomes in Women With Subclinical Hypothyroidism: A Target Trial Emulation
- Desiccated Thyroid Extract Combined With Levothyroxine for TSH Suppression Therapy in DTC (PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- L-thyroxin CI brief — competitive landscape report
- L-thyroxin updates RSS · CI watch RSS
- University of Tartu portfolio CI