Concept Hierarchy & Relationship Mapping
RxNorm Concept Unique Identifier (RxCUI) 29426 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: mecysteine.
The following semantic concepts and normalized strings are associated with this clinical entity:
Type (TTY)
Clinical Name / Synonym
Atom ID
Details
This clinical crossover tool is designed for healthcare professionals, pharmacists, and data analysts to safely compare substitute products and manage medication interoperability.
IN
Ingredient (IN):
Mecysteine
(Atom ID: 436039)
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
mecysteine
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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
436039
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
IN
Ingredient (A compound or moiety that gives the drug its distinctive clinical properties. Ingredients generally use the United States Adopted Name (USAN).)
Source Code
29426
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
PT
Designated preferred name (PT):
Mecysteine
(Atom ID: 10806523)
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
Mecysteine
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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
10806523
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PT
Designated preferred name ()
Source Code
782163002
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
FN
Full form of descriptor (FN):
Mecysteine (substance)
(Atom ID: 10806524)
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
Mecysteine (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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
10806524
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
FN
Full form of descriptor ()
Source Code
782163002
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
PT
Designated preferred name (PT):
Methylcysteine
(Atom ID: 436048)
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
Methylcysteine
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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
436048
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PT
Designated preferred name ()
Source Code
396489003
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
FN
Full form of descriptor (FN):
Methylcysteine (substance)
(Atom ID: 436050)
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
Methylcysteine (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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
436050
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
FN
Full form of descriptor ()
Source Code
396489003
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
PT
Designated preferred name (PT):
Methylcysteine-containing product
(Atom ID: 10807066)
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
Methylcysteine-containing product
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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
10807066
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PT
Designated preferred name ()
Source Code
349993000
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
FN
Full form of descriptor (FN):
Product containing methylcysteine (medicinal product)
(Atom ID: 9259713)
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
Product containing methylcysteine (medicinal product)
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)
29426
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
9259713
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
FN
Full form of descriptor ()
Source Code
349993000
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
RQ6L463N3B - MECYSTEINE (INGREDIENT SUBSTANCE)
RxNorm to Unique Ingredient Identifier crosswalk.
