Hydralazine hydrochloride 25 mg / HCTZ 25 mg Oral Tablet
RxNorm 966594

Concept Hierarchy & Relationship Mapping

RxNorm Concept Unique Identifier (RxCUI) 966594 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: hydralazine hydrochloride 25 mg / HCTZ 25 mg Oral Tablet.

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

SCD
Hydralazine hydrochloride 25 mg / hydrochlorothiazide 25 mg Oral Tablet
Primary clinical definition
AUI:12331065
View
SY
Hydralazine hydrochloride 25 mg / HCTZ 25 mg Oral Tablet
AUI:3068772
View
TMSY
HydrALAZINE hydrochloride 25 mg / HCTZ 25 mg Oral Tablet
AUI:3727562
View
TMSY
HydrALAZINE hydrochloride 25 mg / hydroCHLOROthiazide 25 mg Oral Tablet
AUI:12429785
View

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

SCD

Semantic Clinical Drug (SCD):
Hydralazine hydrochloride 25 mg / hydrochlorothiazide 25 mg Oral Tablet
(Atom ID: 12331065)

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
hydralazine hydrochloride 25 MG / hydrochlorothiazide 25 MG 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)
966594
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12331065
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SCD
Semantic Clinical Drug (Ingredient + Strength + Dose Form)
Source Code
966594
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
{316049} 5487
RXCUI of BOSS Active Ingredient preceded by RXCUI of SCDC responsible for value
RXN AI
{905210} 82027
RXCUI of BOSS Active Ingredient preceded by RXCUI of SCDC responsible for value
RXN AM
{316049} 5487
RXCUI of BOSS Active Moiety preceded by RXCUI of SCDC responsible for value
RXN AM
{905210} 5470
RXCUI of BOSS Active Moiety preceded by RXCUI of SCDC responsible for value
RXN BOSS FROM
{316049} 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
{905210} 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
04/30/2020
Date the RxNorm atom became obsolete
RXTERM FORM
Tab
The RxTerm dose form name for this drug
SY

Synonym (SY):
Hydralazine hydrochloride 25 mg / HCTZ 25 mg Oral Tablet
(Atom ID: 3068772)

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
hydralazine hydrochloride 25 MG / HCTZ 25 MG 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)
966594
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
3068772
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SY
Synonym (Synonym of another TTY, given for clarity.)
Source Code
966594
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.
TMSY

Tall Man Lettering Synonym (TMSY):
HydrALAZINE hydrochloride 25 mg / HCTZ 25 mg Oral Tablet
(Atom ID: 3727562)

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
hydrALAZINE hydrochloride 25 MG / HCTZ 25 MG 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)
966594
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
3727562
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
TMSY
Tall Man Lettering Synonym (Tall Man Lettering synonym of another TTY, given to distinguish between commonly confused drugs.)
Source Code
966594
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.
TMSY

Tall Man Lettering Synonym (TMSY):
HydrALAZINE hydrochloride 25 mg / hydroCHLOROthiazide 25 mg Oral Tablet
(Atom ID: 12429785)

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
hydrALAZINE hydrochloride 25 MG / hydroCHLOROthiazide 25 MG 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)
966594
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12429785
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
TMSY
Tall Man Lettering Synonym (Tall Man Lettering synonym of another TTY, given to distinguish between commonly confused drugs.)
Source Code
966594
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.