RxNorm Related Concepts¶
Retrieves concepts related to a given RxNorm concept (RxCUI) based on a specified relationship type. The node returns a JSON-formatted string containing the input RxCUI, the relationship type, and the related concept data, along with a status message. It handles basic validation and surfaces API errors as status text.
Usage¶
Use this node when you need to explore a drug concept's relationships in RxNorm (e.g., ingredients, dose forms, brand relationships). Provide a single RxCUI and a relationship type to fetch the corresponding related concepts. Commonly used after searching for a drug to navigate its hierarchy or map to related concepts.
Inputs¶
| Field | Required | Type | Description | Example |
|---|---|---|---|---|
| rxcui | True | STRING | The RxNorm Concept Unique Identifier for the source concept to query. Must be a non-empty string representing a single RxCUI. | 313 |
| relationship_type | True | STRING | The RxNorm relationship type to use when finding related concepts. Must be a valid RxNorm relationship keyword. | has_precise_ingredient |
Outputs¶
| Field | Type | Description | Example |
|---|---|---|---|
| related_concepts | STRING | Pretty-printed JSON string containing the input RxCUI, the requested relationship type, and the related concept data returned by the RxNorm service. | { "rxcui": "313", "relationship_type": "has_precise_ingredient", "data": { "...": "..." } } |
| status | STRING | Human-readable status message indicating success or describing an error encountered during the request. | Successfully retrieved has_precise_ingredient for RXCUI 313 |
Important Notes¶
- Input validation: The rxcui input must be a non-empty string; empty values return an error.
- Relationship types: The node does not validate relationship_type values; invalid or unsupported types will result in API errors surfaced in the status output.
- Output format: related_concepts is a JSON string, not a parsed object. Downstream nodes expecting structured data may need to parse it.
- Single concept: This node accepts a single RxCUI, not a list.
- Error propagation: If the underlying service returns an error, the node returns "{}" for related_concepts and an error message in status.
Troubleshooting¶
- Empty output with error status: Verify rxcui is non-empty and a valid RxNorm identifier.
- API Error in status: Check that relationship_type is a valid RxNorm relationship (e.g., has_ingredient, has_precise_ingredient, dose_form_of, tradename_of). Correct the value and retry.
- Unexpected data structure in related_concepts: The output is a JSON string. Ensure downstream steps parse the string before accessing fields.
- No related concepts found: The RxCUI may not have relations of the specified type. Try a different relationship_type or confirm the RxCUI's scope in RxNorm.