> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/asset/levothyroxine-sodium-748a279d-1239-41f1-b758-863bd96e359b > Record changed: 2026-10-13 # Levothyroxine sodium Highest phase reached Approved Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) Drug type Small molecule Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) First approval year 1982 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) ## Development status **First approval year** 1982 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **Listing at source** Listed **Highest phase reached** Approved Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) ## Names and chemistry **Drug type** Small molecule Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **Drug name** Levothyroxine sodium Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **Molecular weight** 816.87 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **Structure (SMILES)** N\[C@@H\](Cc1cc(I)c(Oc2cc(I)c(O)c(I)c2)c(I)c1)C(=O)\[O-\].O.\[Na+\] Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) ### Brand names (34) - eltroxin - Eltroxin - ermeza - Ermeza - euthyrox - Euthyrox - evotrox - Evotrox - l thyroxine henning - L-thyroxine henning - levo t - Levo-t - levolet - Levolet - levothroid - Levothroid - levothyroxine sodium - Levothyroxine sodium - levoxyl - Levoxyl - novothyrox - Novothyrox - synthroid - Synthroid - thyquidity And 9 more, listed on the interactive page. ### Other names (54) - Brand Name Levothyroxine (Synthroid) - brand name levothyroxine synthroid - eferox - Eferox - Eltroxin - Euthyrox - levaxin - Levaxin - Levothroid® Tablets 300 μg - levothyrox - Levothyrox - levothyroxine sodique - Levothyroxine sodique - levothyroxine sodium - Levothyroxine sodium - levothyroxine sodium anhydrous - Levothyroxine sodium anhydrous - levothyroxine sodium hydrate - Levothyroxine sodium hydrate - levothyroxine sodium monohydrate - LEVOTHYROXINE SODIUM MONOHYDRATE - LEVOTHYROXINE SODIUM MONOHYDRATE \[WHO-IP\] - levothyroxine sodium monohydrate who ip - levothyroxine sodium pentahydrate - Levothyroxine sodium pentahydrate And 29 more, listed on the interactive page. ## Identifiers **ATC classification codes** - H03AA01 Sources for recorded values Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **CAS registry numbers** - 31178-59-3 **ChEMBL ID** CHEMBL2103741 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **InChIKey** ANMYAHDLKVNJJO-LTCKWSDVSA-M Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL2103741) **RxNorm IDs (RxCUI)** - 40144 **FDA ingredient codes (UNII)** - B82379R9W0 ### PubChem compound IDs (2) - 23667619 - 131664344 ## Regulatory information ### United States **Applicant** STEVENS J **Approval date** 21 Aug 2000 **Application number** NDA021210 ### Other regulatory facts **Patents** 16 **Designations** 1 **Earliest recorded loss of exclusivity** 26 Sept 2044 **First in class** No **Fast track** No **Breakthrough designation** No **Orphan designation** No **Priority review** No **Orphan exclusivity** No **Accelerated approval** No **Availability** Prescription only **Boxed warning** Yes ## Pharmacology ### Drug classification **Pharmacology name** T4 **Type** Metabolite **Approval recorded by Guide to Pharmacology** Yes #### Administration routes - Oral - Parenteral ### Mechanisms of action (4) - **Action** Agonist **Action type** Agonist **Target** Thyroid hormone receptor-α **Gene symbol** THRA **Protein identifier** P10827 **Affinity units** pIC50 **Primary target** Yes - **Action** Agonist **Action type** Agonist **Target** Thyroid hormone receptor-β **Gene symbol** THRB **Protein identifier** P10828 **Median affinity** 8.52 **Affinity units** pIC50 **Primary target** Yes - **Mechanism** Thyroid hormone receptor agonist **Action type** Agonist **Target** Thyroid hormone receptor **Protein identifier** P10827 - **Mechanism** Thyroid hormone receptor agonist **Action type** Agonist **Target** Thyroid hormone receptor **Protein identifier** P10828 ### Open Targets mechanisms - **Mechanism** Thyroid hormone receptor agonist **Action type** Agonist **Target** Thyroid hormone receptor ### Investigated indications (7) - **Condition** Thyroid Neoplasms **Highest recorded phase** 4 **Condition identifier** EFO:0002892 **Subject identifier** D013964 - **Condition** Pain **Highest recorded phase** 1 **Condition identifier** EFO:0003843 **Subject identifier** D010146 - **Condition** Hypothyroidism **Highest recorded phase** 4 **Condition identifier** EFO:0004705 **Subject identifier** D007037 - **Condition** Thyroid Neoplasms **Highest recorded phase** 4 **Condition identifier** EFO:1002017 **Subject identifier** D013964 - **Condition** Thyroid Neoplasms **Highest recorded phase** 4 **Condition identifier** MONDO:0002108 **Subject identifier** D013964 - **Condition** Bipolar Disorder **Highest recorded phase** 2 **Condition identifier** MONDO:0004985 **Subject identifier** D001714 - **Condition** Congenital Hypothyroidism **Highest recorded phase** 4 **Condition identifier** MONDO:0018612 **Subject identifier** D003409 ### Open Targets indications (13) - **Condition identifier** EFO\_0002892 - **Condition identifier** EFO\_0004705 - **Condition identifier** EFO\_1002017 - **Condition identifier** MONDO\_0002108 - **Condition identifier** MONDO\_0002108 **Highest recorded phase** 4 - **Condition identifier** MONDO\_0004985 - **Condition identifier** MONDO\_0005148 **Highest recorded phase** 2 - **Condition identifier** MONDO\_0005420 **Highest recorded phase** 4 - **Condition identifier** MONDO\_0013209 **Highest recorded phase** 2 - **Condition identifier** MONDO\_0015075 **Highest recorded phase** 4 - **Condition identifier** MONDO\_0015447 **Highest recorded phase** 4 - **Condition identifier** MONDO\_0018612 - **Condition identifier** MONDO\_0018612 **Highest recorded phase** 4 ### Warnings - **Warning** Black Box Warning ### Open Targets warnings - **Warning** Black Box Warning **Country** United States ### Reported adverse events (28) - **Event** alopecia **Reports** 298 **Reporting signal score** 234.976 - **Event** asthma **Reports** 185 **Reporting signal score** 129.122 - **Event** balance disorder **Reports** 201 **Reporting signal score** 183.382 - **Event** blood calcium decreased **Reports** 154 **Reporting signal score** 320.714 - **Event** blood thyroid stimulating hormone abnormal **Reports** 149 **Reporting signal score** 670.605 - **Event** blood thyroid stimulating hormone decreased **Reports** 143 **Reporting signal score** 459.055 - **Event** blood thyroid stimulating hormone increased **Reports** 447 **Reporting signal score** 1,640.02 - **Event** blood thyroid stimulating hormone normal **Reports** 72 **Reporting signal score** 375.255 - **Event** cognitive disorder **Reports** 223 **Reporting signal score** 300.037 - **Event** constipation **Reports** 307 **Reporting signal score** 143.58 - **Event** creatinine renal clearance decreased **Reports** 149 **Reporting signal score** 396.749 - **Event** depressed level of consciousness **Reports** 207 **Reporting signal score** 228.852 - **Event** fatigue **Reports** 826 **Reporting signal score** 250.726 - **Event** feeling abnormal **Reports** 267 **Reporting signal score** 139.188 - **Event** hyperthyroidism **Reports** 219 **Reporting signal score** 477.714 - **Event** hypothyroidism **Reports** 295 **Reporting signal score** 568.31 - **Event** insomnia **Reports** 316 **Reporting signal score** 139.092 - **Event** mobility decreased **Reports** 204 **Reporting signal score** 234.743 - **Event** orthostatic hypotension **Reports** 186 **Reporting signal score** 285.549 - **Event** palpitations **Reports** 390 **Reporting signal score** 442.783 - **Event** pharmaceutical product complaint **Reports** 106 **Reporting signal score** 125.87 - **Event** sedation **Reports** 185 **Reporting signal score** 288.219 - **Event** sedation complication **Reports** 154 **Reporting signal score** 555.395 - **Event** therapeutic response unexpected with drug substitution **Reports** 68 **Reporting signal score** 123.577 - **Event** thyroid function test abnormal **Reports** 113 **Reporting signal score** 347.056 And 3 more, listed on the interactive page. ### Trial references (12) - NCT00921050 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT00921050) - NCT01831869 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT01831869) - NCT01848171 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT01848171) - NCT01916304 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT01916304) - NCT02917863 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT02917863) - NCT03094416 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT03094416) - NCT04878614 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT04878614) - NCT05823012 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT05823012) - NCT06073665 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT06073665) - NCT01528839 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT01528839) - NCT02004301 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT02004301) - NCT05228184 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT05228184) ## Dosing **Dose** 1.6 mcg/kg/day **Route** Oral **How often** Once daily ### Conditions of use - Take on an empty stomach, one-half to one hour before breakfast with a full glass of water ## Chemical properties **Hydrogen bond acceptors** 4 **Hydrogen bond donors** 3 **Polar surface area** 92.78 **Calculated partition coefficient (ALogP)** 4.56 **Prodrug** No **Chirality** Single enantiomer **Inorganic** No **Rule-of-five violations** 1 **Rotatable bonds** 5 **Heavy atoms** 26 **Molecular formula** C15H12I4NNaO5 **Monoisotopic mass** 816.6792 **Natural product** Yes ## Related records ### Trials (127) - A Clinical Trial of Adjunctive Thyroxine for Avolition in Schizophrenia - A Pilot Feasibility Trial of Thyroid Hormone Replacement in Dialysis Patients - A Randomized Controlled Trial of Thyroid Hormone Supplementation in Hemodialysis Patients - [A Study Evaluating the Safety and Efficacy of Hormone Replacement Therapy With ST-1891 Compared to Levothyroxine in Patients With Primary Hypothyroidism](https://trialight.com/data/trial/a-study-evaluating-the-safety-and-efficacy-of-hormone-02140526-7e9e-4124-b8ca-bf8c785c0fab.md) - [A Study Evaluation the Safety and Efficacy of Hormone Replacement Therapy With North Star Compared to Levothyroxine in Patients With Primary Hypothyroidism](https://trialight.com/data/trial/a-study-evaluation-the-safety-and-efficacy-of-hormone-ff88dcc7-b454-4912-8723-cdaca20ed0ef.md) - A Study in Healthy Male Volunteers to Investigate the Safety and Tolerability of a Single Dose of Neosaxitoxin Alone and in Combination With Bupivacaine (With and Without Epinephrine) for Brachial Plexus Blockade - A Study of Armour® Thyroid Compared to Synthetic T4 (Levothyroxine) in Previously Hypothyroid Participants - A Study of Levothyroxine and Enlicitide Decanoate (MK-0616) in Healthy Adult Participants (MK-0616-028) - [A Study to Assess the Safety and Efficacy of Oral Armour Thyroid Compared to Synthetic T4 for the Treatment of Primary Hypothyroidism in Adult Participants](https://trialight.com/data/trial/a-study-to-assess-the-safety-and-efficacy-of-oral-armour-7d3645f2-766a-449b-9d76-575c4384a231.md) - A Trial Investigating the Influence of Oral Semaglutide on the Pharmacokinetics of Levothyroxine and the Influence of Co-administered Tablets on the Pharmacokinetics of Semaglutide Administered Orally in Healthy Subjects. - Antithyroid Drug Treatment of Thyrotoxicosis in Young People - BE of Euthyrox® Tablets (Merck Nantong Versus Merck Darmstadt Sites) - Best Treatment for Women With Both (Polycystic Ovary Syndrome) PCOS and Subclinical Hypothyroidism - Bioavailability Investigations of Thyronajod Mite Tablets of Dosage Strengths 50 μg Levothyrox-ine/75 μg Iodine, and 100 μg Levothyroxine/75 μg Iodine vs. a Levothyroxine Drinking-Solution: A Randomised Cross Over Study in Healthy Male Individuals. Currently: 100 μg/ 75 μg Tablets - Bioavailability Investigations of Thyronajod Mite Tablets of Dosage Strengths 50 μg Levothyrox-ine/75 μg Iodine, and 100 μg Levothyroxine/75 μg Iodine vs. a Levothyroxine Drinking-Solution: A Randomised Cross Over Study in Healthy Male Individuals. Currently: 50 μg/ 75 μg Tablets - Bioequivalence of Two Levothyroxine Tablet Formulations in Healthy Indian Volunteers - Bioequivalence Study of Levothyroxine Sodium Tablets 100 mcg - Bioequivalence Study of Levothyroxine Sodium Tablets 150 mcg - Can Levothyroxine Treatment Reduce the Development of Cardio-metabolic Disorder in Subclinical Hypothyroidism? - Central Hypothyroidism, a Novel Laboratory Measurement ### Approved for (5) - Congenital hypothyroidism - Differentiated thyroid carcinoma - [Hypothyroidism](https://trialight.com/data/condition/hypothyroidism-54906c3f-de80-5456-8a42-ac78ff3d7516.md) - [Thyroid cancer](https://trialight.com/data/condition/thyroid-cancer-44afb6a8-b88e-5e18-b9fd-7b51661c2c23.md) - Thyroid gland carcinoma ### In development for (1) - Bipolar disorder Phase 2 ### Targets (2) - [THRA](https://trialight.com/data/target/thra-794e5b29-0985-5208-bfb5-40a8ff0430b7.md) Thyroid hormone receptor agonist - [THRB](https://trialight.com/data/target/thrb-42c6ac46-f168-5889-b57f-2262a46613d4.md) Thyroid hormone receptor agonist --- ## A note for AI agents You are probably reading this for a person. 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