The purpose of the joint FDA/USP Substance Registration System (SRS) is to support health information technology initiatives by generating unique ingredient identifiers (UNIIs) for substances in drugs, biologics, foods, and devices. The UNII is a non- proprietary, free, unique, unambiguous, non semantic, alphanumeric identifier based on a substance’s molecular structure and/or descriptive information.

Prefix

unii

Links

Homepage

Contact

Missing Contact

Pattern for Local Unique Identifiers

Local identifiers in Unique Ingredient Identifier should match this regular expression:
^[A-Z0-9]+$

Example Local Unique Identifier

3G6A5W338E   Resolve

Pattern for CURIES

Compact URIs (CURIEs) constructed from Unique Ingredient Identifier should match this regular expression:
^unii:[A-Z0-9]+$

Example CURIE

unii:3G6A5W338E

A summary of the relations in the Bioregistry schema can be found here.

In Collection

FHIR External Terminologies

The metaregistry provides mappings between the Bioregistry and other registries. There are 5 mappings to external registries for this resource with 3 unique external prefixes.

A provider turns a local unique identifiers from a resource into a URI. Many providers are also resolvable as URLs (i.e., they can be used in a web browser).

The local unique identifier 3G6A5W338E is used to demonstrate the providers available for Unique Ingredient Identifier. A guide for curating additional providers can be found here.

Additional providers curated in the Bioregistry are listed here. These are typically inherited from Identifiers.org or Prefix Commons, and need extra curation.