Valaciclovir (as valaciclovir hydrochloride) 250 mg oral tablet
RxNorm 427105

Concept Hierarchy & Relationship Mapping

RxNorm Concept Unique Identifier (RxCUI) 427105 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: Valaciclovir (as valaciclovir hydrochloride) 250 mg oral tablet.

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

SCD
Valacyclovir 250 mg Oral Tablet
Primary clinical definition
AUI:1735438
View
FN
Product containing precisely valaciclovir (as valaciclovir hydrochloride) 250 mg/1 each conventional release oral tablet (clinical drug)
AUI:12666122
View
SY
Valaciclovir (as valaciclovir hydrochloride) 250 mg oral tablet
AUI:12666398
View
PT
Valacyclovir (as valacyclovir hydrochloride) 250 mg oral tablet
AUI:12666400
View
TMSY
ValACYclovir 250 mg Oral Tablet
AUI:3739672
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):
Valacyclovir 250 mg Oral Tablet
(Atom ID: 1735438)

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
valacyclovir 250 MG Oral Tablet
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)
427105
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
1735438
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SCD
Semantic Clinical Drug (Ingredient + Strength + Dose Form)
Source Code
427105
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 ACTIVATED
09/01/2021
Date the RxNorm atom was reactivated
RXN AI
{452503} 236081
RXCUI of BOSS Active Ingredient preceded by RXCUI of SCDC responsible for value
RXN AM
{452503} 73645
RXCUI of BOSS Active Moiety preceded by RXCUI of SCDC responsible for value
RXN BOSS FROM
{452503} AM
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
09/14/2005
Date the RxNorm atom became obsolete
RXTERM FORM
Tab
The RxTerm dose form name for this drug
FN

Full form of descriptor (FN):
Product containing precisely valaciclovir (as valaciclovir hydrochloride) 250 mg/1 each conventional release oral tablet (clinical drug)
(Atom ID: 12666122)

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 precisely valaciclovir (as valaciclovir hydrochloride) 250 milligram/1 each conventional release oral tablet (clinical drug)
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)
427105
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12666122
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
FN
Full form of descriptor ()
Source Code
1149474004
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.
SY

Synonym (SY):
Valaciclovir (as valaciclovir hydrochloride) 250 mg oral tablet
(Atom ID: 12666398)

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
Valaciclovir (as valaciclovir hydrochloride) 250 mg oral tablet
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)
427105
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12666398
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SY
Synonym (Synonym of another TTY, given for clarity.)
Source Code
1149474004
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.
PT

Designated preferred name (PT):
Valacyclovir (as valacyclovir hydrochloride) 250 mg oral tablet
(Atom ID: 12666400)

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
Valacyclovir (as valacyclovir hydrochloride) 250 mg oral tablet
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)
427105
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12666400
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
PT
Designated preferred name ()
Source Code
1149474004
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.
TMSY

Tall Man Lettering Synonym (TMSY):
ValACYclovir 250 mg Oral Tablet
(Atom ID: 3739672)

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
valACYclovir 250 MG Oral Tablet
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)
427105
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
3739672
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
427105
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.