Levothyroxine sodium
RxNorm 40144

Concept Hierarchy & Relationship Mapping

RxNorm Concept Unique Identifier (RxCUI) 40144 represents a standardized clinical drug concept used for cross-system interoperability. This concept aggregates multiple Atom IDs (AUIs), which are specific naming variations and synonyms used across pharmaceutical databases to ensure accurate medication mapping for: Levothyroxine sodium.

The following semantic concepts and normalized strings are associated with this clinical entity:

PIN
Levothyroxine sodium
AUI:12254983
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PT
Levothyroxine sodium
AUI:480563
View
FN
Levothyroxine sodium (substance)
AUI:480589
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This clinical crossover tool is designed for healthcare professionals, pharmacists, and data analysts to safely compare substitute products and manage medication interoperability.

PINPrescribable

Precise Ingredient (PIN):
Levothyroxine sodium
(Atom ID: 12254983)

Clinical Status & Identity

Prescribable Status
YES (Active)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
levothyroxine sodium
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
N
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
40144
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12254983
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PIN
Precise Ingredient (A specified form of the ingredient that may or may not be clinically active. Most precise ingredients are salt or isomer forms.)
Source Code
40144
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
RxNorm Vocabulary (RXNORM)
The official name and abbreviation for the vocabulary source.
Source Version
20AA_260601F
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
RxNorm Customer Service, , U.S. National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, (888) FIND-NLM, , https://support.nlm.nih.gov/support/create-case/, https://www.nlm.nih.gov/research/umls/rxnorm/
Source licensing contact information.
UNII Crosswalk
9J765S329G - LEVOTHYROXINE SODIUM (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
PTPrescribable

Designated preferred name (PT):
Levothyroxine sodium
(Atom ID: 480563)

Clinical Status & Identity

Prescribable Status
YES (Active)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Levothyroxine sodium
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
N
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
40144
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
480563
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PT
Designated preferred name ()
Source Code
126202002
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
US Edition of SNOMED CT (SNOMEDCT_US)
The official name and abbreviation for the vocabulary source.
Source Version
2026_01_31
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
National Library Of Medicine, NLM is a Charter Member of SNOMED International on behalf of the U.S., National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, 1-888-FIND-NLM (1-888-346-3656), , https://support.nlm.nih.gov/support/create-case/,
Source licensing contact information.
UNII Crosswalk
9J765S329G - LEVOTHYROXINE SODIUM (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
FNPrescribable

Full form of descriptor (FN):
Levothyroxine sodium (substance)
(Atom ID: 480589)

Clinical Status & Identity

Prescribable Status
YES (Active)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Levothyroxine sodium (substance)
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
N
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
40144
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
480589
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
FN
Full form of descriptor ()
Source Code
126202002
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
US Edition of SNOMED CT (SNOMEDCT_US)
The official name and abbreviation for the vocabulary source.
Source Version
2026_01_31
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
National Library Of Medicine, NLM is a Charter Member of SNOMED International on behalf of the U.S., National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, 1-888-FIND-NLM (1-888-346-3656), , https://support.nlm.nih.gov/support/create-case/,
Source licensing contact information.
UNII Crosswalk
9J765S329G - LEVOTHYROXINE SODIUM (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.

Patient Education

Levothyroxine


Levothyroxine is used to treat hypothyroidism (condition where the thyroid gland does not produce enough thyroid hormone). It is also used with surgery and radioactive iodine therapy to treat thyroid cancer. Levothyroxine is in a class of medications called hormones. It works by replacing thyroid hormone that is normally produced by the body. Without thyroid hormone, your body cannot function properly, which may result in poor growth, slow speech, lack of energy, excessive tiredness, constipation, weight gain, hair loss, dry, thick skin, increased sensitivity to cold, joint and muscle pain, heavy or irregular menstrual periods, and depression. When taken correctly, levothyroxine reverses these symptoms.
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