APIs

RxNorm API

getRelatedByRelationship

Information returned
Concepts directly related to a specified concept by a specified relationship
Service domain
https://rxnav.nlm.nih.gov
HTTP request
GET  /REST/rxcui/rxcui/related.xml?rela=yourRelas&expand=fields

Description

Get RxNorm concepts related to concept rxcui by relationships specified by the rela parameter.

Scope

Active: concepts in the current RxNorm data set that have an atom with SAB=RXNORM and SUPPRESS=N

Parameters

ParameterLocationUseDescriptionDefault
rxcuiPathRequiredRxNorm identifier
formatPathOptional

Notation for results

One of:
.xml
Get results in XML
.json
Get results in JSON
.xml
relaQueryRequiredRelationship(s)

(Space-separated list. See getRelaTypes for the menu.)

expandQueryOptionalAdditional result fields to retrieve
One or more of:
psn
Prescribable Name (PSN)

(Space-separated list.)

Note that HTTP requires that query parameters be "URL encoded". For instance, a "space-separated list" will, in practice, usually appear to use either a plus sign (+) or %20 as the separator. For full information on URL encoding, please refer to IETF RFC 3986, "Uniform Resource Identifier".

Output structure

Results are available as either XML or JSON.

  • The XML result has the root element rxnormdata. It is described in the XML Schema for the RxNorm API; the relevant element structure is summarized below. Elements that would be empty might be left out.

  • The JSON result is an object {...}, analogous to the content of the XML rxnormdata. Fields that might occur multiple times in the XML are expressed as an array. Fields that would be empty might be null or left out. Numbers are expressed as strings.

Both XML and JSON results follow the same outline:

rxnormdata
Root element in XML, or anonymous object in JSON
relatedGroup
rxcui
(Always empty)
conceptGroup (array)
Related concepts having a certain TTY
tty
Term type of the concepts in this group
conceptProperties (array)
Related concept
rxcui
RxNorm identifier
name
RxNorm concept name
synonym
Short or "Tallman" RxNorm synonym
tty
Term type
language
LAT attribute from RxNorm
suppress
SUPPRESS field from RxNorm
umlscui
(Always empty)
psn
Prescribable Name

Example: Concepts related by "tradename_of" or "has_precise_ingredient" to Plavix (RxCUI=174742)

XML: https://rxnav.nlm.nih.gov/REST/rxcui/174742/related?rela=tradename_of+has_precise_ingredient

JSON: https://rxnav.nlm.nih.gov/REST/rxcui/174742/related.json?rela=tradename_of+has_precise_ingredient

An XML result is shown below.

<rxnormdata>
    <relatedGroup>
        ...
        <conceptGroup>
            <tty>IN</tty>
            <conceptProperties>
                <rxcui>32968</rxcui>
                <name>clopidogrel</name>
                <synonym/>
                <tty>IN</tty>
                <language>ENG</language>
                <suppress>N</suppress>
                <umlscui/>
            </conceptProperties>
        </conceptGroup>
        <conceptGroup>
            <tty>PIN</tty>
            <conceptProperties>
                <rxcui>236991</rxcui>
                <name>clopidogrel bisulfate</name>
                <synonym/>
                <tty>PIN</tty>
                <language>ENG</language>
                <suppress>N</suppress>
                <umlscui/>
            </conceptProperties>
        </conceptGroup>
    </relatedGroup>
</rxnormdata>