UNITHROID (levothyroxine sodium)
Unithroid is a synthetic thyroid hormone used to restore normal hormone levels in adults and children with various forms of hypothyroidism. It helps patients whose low thyroid levels stem from issues with the thyroid gland, pituitary gland, or hypothalamus, whether the condition was present at birth or developed later. The medication is also used as an additional therapy following surgery or radioiodine treatment to help manage certain types of thyroid cancer.
How UNITHROID Works
This medication works by diffusing into cell nuclei and binding to thyroid receptor proteins on the DNA, which activates the production of essential proteins and messenger RNA. While the drug provides T4, the body converts most of it into T3 in peripheral tissues to produce its physiological effects. This process allows the hormone to control gene transcription and maintain normal body functions.
Details
- Status
- Prescription
- First Approved
- 2000-08-21
- Routes
- ORAL
- Dosage Forms
- TABLET
UNITHROID Approval History
What UNITHROID Treats
2 indicationsUNITHROID is approved for 2 conditions since its original approval in 2000. These indications span multiple therapeutic areas including oncology, immunology, and more.
- Hypothyroidism
- Thyroid Cancer
UNITHROID Boxed Warning
NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS Thyroid hormones, including UNITHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their a...
WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS Thyroid hormones, including UNITHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects [see Adverse Reactions ( 6 ), Drug Interactions ( 7.7 ), and Overdosage ( 10 )] . WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS See full prescribing information for complete boxed warning. Thyroid hormones, including UNITHROID, should not be used for the treatment of obesity or for weight loss. Doses beyond the range of daily hormonal requirements may produce serious or even life threatening manifestations of toxicity ( 6 , 10 ).
UNITHROID Competitive Set
ProThree rings of competition based on shared molecular targets and treated indications.
Direct competitors
Same target(s) AND same indication — head-to-head.
Indication competitors
Same indication, different mechanism — what else might this patient receive?
Filters applied: drops same-active-ingredient (505(b)(2) reformulations), route-mismatch (topical vs systemic), and cross-therapeutic-area matches in same-indication rings.
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Clinical Trial Registry
6 trials| Trial | Sponsor ID | Phase | Status | Title |
|---|---|---|---|---|
| NCT06073665 DOT4 | 1R01AG081698-01, #853300 R01AG081698 | Ph 4 | recruiting | Dosing of LT4 in Older Individuals |
| NCT05228184 | 20US-T414 | Ph 4 | terminated | Use of Tirosint®-SOL or Tablet Formulations of Levothyroxine in Pediatric Patients With Congenital Hypothyroidism (CH) |
| NCT05823012 results posted | XP-8121-120 | Ph 2 | completed | Study of XP-8121 For the Treatment of Adult Subjects With Hypothyroidism |
| NCT04878614 | IRB#20-002097 | Ph 4 | terminated | Comparison of Levothyroxine Formulation in Hypothyroid Patients With Enteral Feeding |
| NCT03281083 | MRN-01-NAFLD-01 | Ph 2 | terminated | Levothyroxine for Non-Alcoholic Fatty Liver Disease (NAFLD) |
| NCT00921050 | EN_LC_P136 | Ph 2, Ph 3 | completed | Subclinical Hypothyroidism and Mind in the Elderly |
Active Pipeline
Ongoing clinical trials by development phase
Key Completed Trials
Completed studies with published results, ranked by significance
Trial Timeline
Full development history with FDA approval milestones
Understanding FDA Approval Types
| Count | Type | What it means |
|---|---|---|
| - | ORIG | Original approval - drug first enters market |
| - | SUPPL - Efficacy | New indication (new disease/condition approved) |
| - | SUPPL - Labeling | Label text changes (warnings, dosing updates) |
| - | SUPPL - Manufacturing | Production changes (new facility) |
| - | SUPPL - Chemistry | Formulation changes (new dosage strength) |
Green lines in the timeline show ORIG and Efficacy approvals - the clinically meaningful milestones.
UNITHROID FDA Label Details
Indications & Usage
FDA Label (PDF)UNITHROID is indicated for the treatment of Hypothyroidism; Thyroid Cancer.
WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS Thyroid hormones, including UNITHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss. In euthyroid patients, doses within the range of daily hormonal requirements are ineffect...
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Data Sources
Data sourced from official FDA and NIH databases. Click links to verify on original sources.