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1365000

USP

Levothyroxine

United States Pharmacopeia (USP) Reference Standard

Synonym(s):

L-Thyroxine, 3,3′,5,5″-Tetraiodo-L-thyronine, 3-[4-(4-Hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]-L-alanine, T4

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About This Item

Linear Formula:
HOC6H2(I)2OC6H2(I)2CH2CH(NH2)CO2H
CAS Number:
Molecular Weight:
776.87
Beilstein:
2228515
MDL number:
UNSPSC Code:
41116107
PubChem Substance ID:
NACRES:
NA.24

grade

pharmaceutical primary standard

API family

levothyroxine

manufacturer/tradename

USP

mp

223 °C (dec.) (lit.)

application(s)

pharmaceutical (small molecule)

format

neat

SMILES string

N[C@@H](Cc1cc(I)c(Oc2cc(I)c(O)c(I)c2)c(I)c1)C(O)=O

InChI

1S/C15H11I4NO4/c16-8-4-7(5-9(17)13(8)21)24-14-10(18)1-6(2-11(14)19)3-12(20)15(22)23/h1-2,4-5,12,21H,3,20H2,(H,22,23)/t12-/m0/s1

InChI key

XUIIKFGFIJCVMT-LBPRGKRZSA-N

Gene Information

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General description

This product is provided as delivered and specified by the issuing Pharmacopoeia. All information provided in support of this product, including SDS and any product information leaflets have been developed and issued under the Authority of the issuing Pharmacopoeia. For further information and support please go to the website of the issuing Pharmacopoeia.

Application

Levothyroxine USP reference standard, intended for use in specified quality tests and assays as specified in the USP compendia. Also, for use with USP monographs such as:
  • Levothyroxine Sodium
  • Levothyroxine Sodium Tablets
  • Levothyroxine Sodium Oral Powder
  • Liothyronine Sodium
  • Thyroid
  • Thyroid Tablets
  • Liothyronine Sodium Tablets

Biochem/physiol Actions

L-Thyroxine (T4) and triiodo-L-thyronine (T3) are iodine-containing hormones produced from thyroglobulin in the thyroid follicular cells. The stimulation of metabolic rate and regulation of growth and development by these hormones appear to be due to their effects on DNA transcription and, thus, protein synthesis.

Analysis Note

These products are for test and assay use only. They are not meant for administration to humans or animals and cannot be used to diagnose, treat, or cure diseases of any kind.  ​

Other Notes

Sales restrictions may apply.

Pictograms

Health hazard

Signal Word

Danger

Hazard Statements

Precautionary Statements

Hazard Classifications

STOT RE 1

Target Organs

Thyroid,Cardio-vascular system,Kidney

Storage Class Code

6.1C - Combustible acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable


Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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Levothyroxine Sodium
United States Pharmacopeia, 45(2) (2020)
Levothyroxine Sodium Tablets
United States Pharmacopeia, 39(1), 3418-3418 (2023)
B Velkeniers et al.
Human reproduction update, 19(3), 251-258 (2013-01-19)
BACKGROUND Previous meta-analyses of observational data indicate that pregnant women with subclinical hypothyroidism have an increased risk of adverse pregnancy outcome. Potential benefits of levothyroxine (LT4) supplementation remain unclear, and no systematic review or meta-analysis of trial findings is available
Michaela Granfors et al.
Obstetrics and gynecology, 124(1), 10-15 (2014-06-06)
To evaluate the efficacy of a targeted thyroid testing approach during pregnancy in clinical practice. This is a retrospective cohort study performed within Uppsala County, Sweden. Data were derived from the population-based Uppsala Biobank of Pregnant Women, in which blood
Shannon E Scratch et al.
Pediatrics, 133(4), e955-e963 (2014-04-02)
Preterm infants commonly have transient hypothyroxinemia of prematurity after birth, which has been associated with deficits in general intellectual functioning, memory, attention, and academic achievement. However, research has predominantly focused on thyroxine levels in the first 2 weeks of life

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