Levothroid
- Levothyroxine sodium
- L-Thyroxine sodium
- 55-03-8
- Euthyrox
- Unithroid
- Create:2008-02-05
- Modify:2025-01-25
- 3,5,3',5'-Tetraiodothyronine
- Berlthyrox
- Dexnon
- Eferox
- Eltroxin
- Eltroxine
- Euthyrox
- Eutirox
- L Thyrox
- L Thyroxin beta
- L Thyroxin Henning
- L Thyroxine
- L Thyroxine Roche
- L-3,5,3',5'-Tetraiodothyronine
- L-Thyrox
- L-Thyroxin beta
- L-Thyroxin Henning
- L-Thyroxine
- L-Thyroxine Roche
- Lévothyrox
- Levo T
- Levo-T
- Levothroid
- Levothyroid
- Levothyroxin Deladande
- Levothyroxin Delalande
- Levothyroxine
- Levothyroxine Sodium
- Levoxine
- Levoxyl
- Novothyral
- Novothyrox
- O-(4-Hydroxy-3,5-diiodophenyl) 3,5-diiodo-L-tyrosine
- O-(4-Hydroxy-3,5-diiodophenyl)-3,5-diiodotyrosine
- Oroxine
- Sodium Levothyroxine
- Synthroid
- Synthrox
- T4 Thyroid Hormone
- Thevier
- Thyrax
- Thyroid Hormone, T4
- Thyroxin
- Thyroxine
- Tiroidine
- Tiroxina Leo
- Unithroid
- Levothyroxine sodium
- L-Thyroxine sodium
- 55-03-8
- Euthyrox
- Unithroid
- levothroid
- Levoxyl
- Novothyrox
- Letter
- Oroxine
- Sodium levothyroxine
- Sodium thyroxinate
- eltroxin
- L-Thyroxine sodium salt
- Sodium L-thyroxine
- synthroid
- Laevoxin
- Thyroxevan
- Levaxin
- Thyroxine sodium
- l-Thyroxine monosodium salt
- Levothyroxine sodium anhydrous
- Levothyroxine sodique
- Levolet
- Tirosint
- Levothyroxinum natricum
- Levo-T
- Thyroxine sodium salt
- Eferox
- Sodium thyroxine
- 25416-65-3
- Thyro-Tabs
- Dathroid
- Levothyrox
- Soloxine
- levotiroxina de sodio
- 3,3',5,5'-Tetraiodo-L-thyronine, sodium salt
- Levoroxine
- Roxstan
- Sodium thyroxin
- Ro-thyroxine
- L-Thyroxine (sodium)
- Synthroid sodium
- Sodium l-thyroxin
- 054I36CPMN
- CHEBI:6446
- Thyroxin sodium
- Levothyroxine sodium hydrate
- L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salt
- Tirosint-Sol
- Tetroid
- Thyradin
- Tiroidina
- Tyrosint
- L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodiumsalt
- Thyradin S
- Thyroxine sodique
- Levothyroxine sodium (INN)
- Thyroxinum natricum
- Sodium-L-thyroxine
- Levothyroxin-natrium
- Berlthyrox
- L-Thyroxine sodium xhydrate
- Thyroxinique
- Leventa
- LEVOTHYROXINE SODIUM [INN]
- Thevier
- Thyrosit
- Thyrax Sodium
- sodium (2S)-2-amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]propanoate
- Levotiroxina sodica
- NSC-259940
- Levotiroxina sodica [INN-Spanish]
- Levothyroxine sodique [INN-French]
- EINECS 200-221-4
- Levothyroxinum natricum [INN-Latin]
- NSC 259940
- Levothyroxine sodium tablets
- UNII-054I36CPMN
- Thyroxine, monosodium salt, L-
- Levothyroxine Sodium [USAN:INN]
- MFCD00002596
- Thyroxine Soduim Salt
- Epitope ID:136776
- SCHEMBL34102
- Levothyroxine sodium;T4 sodium
- DTXSID90883228
- L-Thyroxine (sodium) (Standard)
- HY-18341BR
- THYROXINE SODIUM SALT [MI]
- sodium 4-o-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-l-tyrosine
- Levothyroxine for peak identification
- AC-919
- HY-18341B
- LEVOTHYROXINE SODIUM [WHO-DD]
- AKOS015918420
- AKOS024284731
- CCG-270489
- AC-10210
- AS-83570
- DA-65088
- CS-0031276
- NS00081517
- T0245
- C08212
- D11113
- LEVOTHYROXINE SODIUM ANHYDROUS [WHO-IP]
- J-524276
- Q27107208
- LEVOTHYROXINUM NATRICUM ANHYDROUS [WHO-IP LATIN]
- Z1551967075
- L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, sodium salt (1:1)
- Sodium (S)-2-Amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]propionate
- sodium;(2S)-2-amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]propanoate
- (S)-2-Amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]propionic Acid Sodium Salt
Use (kg) in Switzerland (2009): >5
Use (kg; approx.) in Germany (2009): >100
Use (kg) in USA (2002): 173
Use (kg) in France (2004): 59
Consumption (g per capita) in Switzerland (2009): 0.00064
Consumption (g per capita; approx.) in Germany (2009): 0.0012
Consumption (g per capita) in the USA (2002): 0.00061
Consumption (g per capita) in France (2004): 0.00098
Excretion rate: 0.5
Calculated removal (%): 35.8
H361 (94.2%): Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]
H372 (94.2%): Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]
P203, P260, P264, P270, P280, P318, P319, P405, and P501
(The corresponding statement to each P-code can be found at the GHS Classification page.)
Aggregated GHS information provided per 52 reports by companies from 4 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.
Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown.
Repr. 2 (94.2%)
STOT RE 1 (94.2%)
STOT RE 1 (75%)
STOT RE 2 (25%)
IMAP assessments - L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salt: Human health tier I assessment
IMAP assessments - L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salt: Environment tier I assessment
◉ Summary of Use during Lactation
Levothyroxine (T4) is a normal component of human milk. Limited data on exogenous replacement doses of levothyroxine during breastfeeding indicate no adverse effects in infants. The American Thyroid Association recommends that subclinical and overt hypothyroidism should be treated with levothyroxine in lactating women seeking to breastfeed. Adequate levothyroxine treatment during lactation may normalize milk production in hypothyroid lactating mothers with low milk supply. Levothyroxine dosage requirement may be increased in the postpartum period compared to prepregnancy requirements in patients with Hashimoto's thyroiditis.
◉ Effects in Breastfed Infants
Effects of exogenous thyroid hormone administration to mothers on their infant have not been reported. One case of apparent mitigation of cretinism in hypothyroid infants by breastfeeding has been reported, but the amounts of thyroid hormones in milk are not optimal, and this result has been disputed. The thyroid hormone content of human milk from the mothers of very preterm infants appears not to be sufficient to affect the infants' thyroid status. The amounts of thyroid hormones in milk are apparently not sufficient to interfere with diagnosis of hypothyroidism.
In a telephone follow-up study, 5 nursing mothers reported taking levothyroxine (dosage unspecified). The mothers reported no adverse reactions in their infants.
One mother who had undergone a thyroidectomy was taking levothyroxine 100 mcg daily as well as calcium carbonate and calcitriol. Her breastfed infant was reportedly "thriving" at 3 months of age.
A woman with propionic acidemia took levothyroxine 50 mcg daily as well as biotin, carnitine, and various amino acids while exclusively breastfeeding her infant for 2 months and nonexclusively for 10 months. At that time, the infant had normal growth and development.
◉ Effects on Lactation and Breastmilk
Adequate thyroid hormone serum levels are required for normal lactation. Replacing deficient thyroid levels should improve milk production caused by hypothyroidism. Supraphysiologic doses would not be expected to further improve lactation.
◉ Summary of Use during Lactation
Thyroid is an animal-derived mixture of levothyroxine (T4) and liothyronine (T3), which are normal components of human milk. Limited data on exogenous replacement doses of levothyroxine during breastfeeding indicate no adverse effects in infants. If thyroid is required by the mother, it is not a reason to discontinue breastfeeding. The American Thyroid Association recommends that subclinical and overt hypothyroidism should be treated with levothyroxine in lactating women seeking to breastfeed. Thyroid dosage requirement may be increased in the postpartum period compared to prepregnancy requirements patients with Hashimoto's thyroiditis.
◉ Effects in Breastfed Infants
Effects of exogenous thyroid hormone administration to mothers on their infant have not been reported. One case of apparent mitigation of cretinism in hypothyroid infants by breastfeeding has been reported, but the amounts of thyroid hormones in milk are not optimal, and this result has been disputed. The thyroid hormone content of human milk from the mothers of very preterm infants appears not to be sufficient to affect the infants' thyroid status. The amounts of thyroid hormones in milk are apparently not sufficient to interfere with diagnosis of hypothyroidism.
In a telephone follow-up study, 5 nursing mothers reported taking levothyroxine (dosage unspecified). The mothers reported no adverse reactions in their infants.
One mother with who had undergone a thyroidectomy was taking levothyroxine 100 mcg daily as well as calcium carbonate and calcitriol. Her breastfed infant was reportedly "thriving" at 3 months of age.
◉ Effects on Lactation and Breastmilk
Adequate thyroid hormone serum levels are required for normal lactation. Replacing deficient thyroid levels should improve milk production caused by hypothyroidism. Supraphysiologic doses would not be expected to further improve lactation.
Patents are available for this chemical structure:
https://patentscope.wipo.int/search/en/result.jsf?inchikey=YDTFRJLNMPSCFM-YDALLXLXSA-M
- Australian Industrial Chemicals Introduction Scheme (AICIS)L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salthttps://services.industrialchemicals.gov.au/search-assessments/
- ChemIDplusLevothyroxine Sodium [USAN:INN]https://pubchem.ncbi.nlm.nih.gov/substance/?source=chemidplus&sourceid=0000055038ChemIDplus Chemical Information Classificationhttps://pubchem.ncbi.nlm.nih.gov/source/ChemIDplus
- EPA Chemicals under the TSCAL-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, sodium salt (1:1)https://www.epa.gov/chemicals-under-tscaEPA TSCA Classificationhttps://www.epa.gov/tsca-inventory
- EPA DSSToxL-Thyroxine monosodium salthttps://comptox.epa.gov/dashboard/DTXSID90883228CompTox Chemicals Dashboard Chemical Listshttps://comptox.epa.gov/dashboard/chemical-lists/
- European Chemicals Agency (ECHA)LICENSEUse of the information, documents and data from the ECHA website is subject to the terms and conditions of this Legal Notice, and subject to other binding limitations provided for under applicable law, the information, documents and data made available on the ECHA website may be reproduced, distributed and/or used, totally or in part, for non-commercial purposes provided that ECHA is acknowledged as the source: "Source: European Chemicals Agency, http://echa.europa.eu/". Such acknowledgement must be included in each copy of the material. ECHA permits and encourages organisations and individuals to create links to the ECHA website under the following cumulative conditions: Links can only be made to webpages that provide a link to the Legal Notice page.https://echa.europa.eu/web/guest/legal-noticeLevothyroxine sodiumhttps://echa.europa.eu/substance-information/-/substanceinfo/100.000.202L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salt, hydratehttps://echa.europa.eu/substance-information/-/substanceinfo/100.211.289Levothyroxine sodium (EC: 200-221-4)https://echa.europa.eu/information-on-chemicals/cl-inventory-database/-/discli/details/91357L-Tyrosine, O-(4-hydroxy-3,5-diiodophenyl)-3,5-diiodo-, monosodium salt, hydrate (EC: 685-634-1)https://echa.europa.eu/information-on-chemicals/cl-inventory-database/-/discli/details/216340
- FDA Global Substance Registration System (GSRS)LICENSEUnless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.https://www.fda.gov/about-fda/about-website/website-policies#linkingLEVOTHYROXINE SODIUM ANHYDROUShttps://gsrs.ncats.nih.gov/ginas/app/beta/substances/054I36CPMN
- ChEBILevothyroxine sodium anhydroushttps://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:6446
- NCI Thesaurus (NCIt)LICENSEUnless otherwise indicated, all text within NCI products is free of copyright and may be reused without our permission. Credit the National Cancer Institute as the source.https://www.cancer.gov/policies/copyright-reuseNCI Thesaurushttps://ncit.nci.nih.gov
- ClinicalTrials.govLICENSEThe ClinicalTrials.gov data carry an international copyright outside the United States and its Territories or Possessions. Some ClinicalTrials.gov data may be subject to the copyright of third parties; you should consult these entities for any additional terms of use.https://clinicaltrials.gov/ct2/about-site/terms-conditions#Use
- DailyMed
- Drugs and Lactation Database (LactMed)Levothyroxinehttps://www.ncbi.nlm.nih.gov/books/n/lactmed/LM158/
- Drugs@FDALICENSEUnless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.https://www.fda.gov/about-fda/about-website/website-policies#linking
- EU Clinical Trials Register
- FDA Approved Animal Drug Products (Green Book)LICENSEUnless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.https://www.fda.gov/about-fda/about-website/website-policies#linking
- FDA Orange BookLICENSEUnless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.https://www.fda.gov/about-fda/about-website/website-policies#linking
- KEGGLICENSEAcademic users may freely use the KEGG website. Non-academic use of KEGG generally requires a commercial licensehttps://www.kegg.jp/kegg/legal.htmlUSP drug classificationhttp://www.genome.jp/kegg-bin/get_htext?br08302.kegAnatomical Therapeutic Chemical (ATC) classificationhttp://www.genome.jp/kegg-bin/get_htext?br08303.kegTarget-based classification of drugshttp://www.genome.jp/kegg-bin/get_htext?br08310.keg
- National Drug Code (NDC) DirectoryLICENSEUnless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.https://www.fda.gov/about-fda/about-website/website-policies#linking
- NLM RxNorm TerminologyLICENSEThe RxNorm Terminology is created by the National Library of Medicine (NLM) and is in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from NLM. Credit to the U.S. National Library of Medicine as the source is appreciated but not required. The full RxNorm dataset requires a free license.https://www.nlm.nih.gov/research/umls/rxnorm/docs/termsofservice.htmllevothyroxine sodiumhttps://rxnav.nlm.nih.gov/id/rxnorm/40144levothyroxine sodium anhydroushttps://rxnav.nlm.nih.gov/id/rxnorm/1372638
- NORMAN Suspect List ExchangeLICENSEData: CC-BY 4.0; Code (hosted by ECI, LCSB): Artistic-2.0https://creativecommons.org/licenses/by/4.0/LEVOTHYROXINE SODIUMNORMAN Suspect List Exchange Classificationhttps://www.norman-network.com/nds/SLE/
- Springer Nature
- WHO Anatomical Therapeutic Chemical (ATC) ClassificationLICENSEUse of all or parts of the material requires reference to the WHO Collaborating Centre for Drug Statistics Methodology. Copying and distribution for commercial purposes is not allowed. Changing or manipulating the material is not allowed.https://www.whocc.no/copyright_disclaimer/Levothyroxine sodiumhttps://www.whocc.no/atc_ddd_index/?code=H03AA01
- Wikidatalevothyroxine sodiumhttps://www.wikidata.org/wiki/Q27107208
- Medical Subject Headings (MeSH)LICENSEWorks produced by the U.S. government are not subject to copyright protection in the United States. Any such works found on National Library of Medicine (NLM) Web sites may be freely used or reproduced without permission in the U.S.https://www.nlm.nih.gov/copyright.html
- PubChem
- GHS Classification (UNECE)GHS Classification Treehttp://www.unece.org/trans/danger/publi/ghs/ghs_welcome_e.html
- EPA Substance Registry ServicesEPA SRS List Classificationhttps://sor.epa.gov/sor_internet/registry/substreg/LandingPage.do
- PATENTSCOPE (WIPO)SID 388553193https://pubchem.ncbi.nlm.nih.gov/substance/388553193