Thyrolar 1 (12.5 mcg / 50 mcg) Oral Tablet
RxNorm 903442

Concept Hierarchy & Relationship Mapping

RxNorm Concept Unique Identifier (RxCUI) 903442 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: Thyrolar 1 (12.5 mcg / 50 mcg) Oral Tablet.

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

SBD
Levothyroxine sodium 0.05 mg / liothyronine sodium 0.0125 mg Oral Tablet [Thyrolar]
AUI:12357985
View
PSN
Thyrolar 1 (12.5 mcg / 50 mcg) Oral Tablet
AUI:6361191
View
SY
Thyrolar 1 (levothyroxine sodium 50 mcg / liothyronine sodium 12.5 mcg) Oral Tablet
AUI:3064993
View

This clinical crossover tool is designed for healthcare professionals, pharmacists, and data analysts to safely compare substitute products and manage medication interoperability.

SBD

Semantic Branded Drug (SBD):
Levothyroxine sodium 0.05 mg / liothyronine sodium 0.0125 mg Oral Tablet [Thyrolar]
(Atom ID: 12357985)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
levothyroxine sodium 0.05 MG / liothyronine sodium 0.0125 MG Oral Tablet [Thyrolar]
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
903442
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12357985
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SBD
Semantic Branded Drug (Ingredient + Strength + Dose Form + Brand Name)
Source Code
903442
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.

Technical Attributes & Logic

RXN AI
{903436} 40144
RXCUI of BOSS Active Ingredient preceded by RXCUI of SCDC responsible for value
RXN AI
{903437} 142448
RXCUI of BOSS Active Ingredient preceded by RXCUI of SCDC responsible for value
RXN AM
{903436} 10582
RXCUI of BOSS Active Moiety preceded by RXCUI of SCDC responsible for value
RXN AM
{903437} 10814
RXCUI of BOSS Active Moiety preceded by RXCUI of SCDC responsible for value
RXN BOSS FROM
{903436} AI
Source of BOSS as either from the active ingredient (AI) or the active moiety (AM) preceded by RXCUI of SCDC responsible for value
RXN BOSS FROM
{903437} AI
Source of BOSS as either from the active ingredient (AI) or the active moiety (AM) preceded by RXCUI of SCDC responsible for value
RXN OBSOLETED
04/28/2026
Date the RxNorm atom became obsolete
RXTERM FORM
Tab
The RxTerm dose form name for this drug
PSN

Prescribable Name (PSN):
Thyrolar 1 (12.5 mcg / 50 mcg) Oral Tablet
(Atom ID: 6361191)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Thyrolar 1 (12.5 MCG / 50 MCG) Oral Tablet
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
903442
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
6361191
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PSN
Prescribable Name (Synonym of another TTY, given for clarity and for display purposes in electronic prescribing applications. Only one PSN per concept.)
Source Code
903442
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.
SY

Synonym (SY):
Thyrolar 1 (levothyroxine sodium 50 mcg / liothyronine sodium 12.5 mcg) Oral Tablet
(Atom ID: 3064993)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Thyrolar 1 (levothyroxine sodium 50 MCG / liothyronine sodium 12.5 MCG) Oral Tablet
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
903442
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
3064993
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SY
Synonym (Synonym of another TTY, given for clarity.)
Source Code
903442
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.

Patient Education

Liotrix


Liotrix is used to treat hypothyroidism (a condition that results when the thyroid gland does not produce enough thyroid hormone). Symptoms of hypothyroidism include lack of energy, depression, constipation, weight gain, hair loss, dry skin, dry coarse hair, muscle cramps, decreased concentration, aches and pains, swelling of the legs, and increased sensitivity to cold. When taken correctly, liotrix can reverse these symptoms. Liotrix is also used to treat goiter (enlarged thyroid gland). This medication is also used to test for hyperthyroidism (a condition where the thyroid gland produces too much thyroid hormone). Liotrix is in a class of medications called thyroid agents. It works by supplying the thyroid hormones normally produced by the body.
[Learn More]


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