APIs

Drug Interaction API

findInteractionsFromList

Information returned
Interactions between a list of drugs
Service domain
https://rxnav.nlm.nih.gov
HTTP request
GET  /REST/interaction/list.xml?rxcuis=rxcuis&sources=sources

Description

Get the drug interactions between drugs in a list.

The RxNorm identifiers can represent ingredients (e.g. simvastatin), brand names (e.g. Tylenol) or branded or clinical drugs (e.g. Morphine 50 mg oral tablet).

Currently, the API uses two sources for its interaction information - ONCHigh and DrugBank.

ONCHigh is a list of high-priority drug-drug interactions derived by a panel of experts and contained in a JAMIA article. ONCHigh is updated using CredibleMeds with drugs that have a known risk of Torsades de Pointes (TdP).

DrugBank drug-drug interaction information is drawn from the DrugBank database. The data shared with us by DrugBank do not carry severity information.

Additional information is returned for these interactions relating the ingredient level components with each other both in RxNorm and in the source (DrugBank) where the interaction was defined.

Upcoming Changes On or After August 2, 2021:

Parameters

ParameterLocationUseDescriptionDefault
formatPathOptional

Notation for results

One of:
.xml
Get results in XML
.json
Get results in JSON
.xml
rxcuisQueryRequiredRxNorm identifier

(Space-separated list. At most 50 items.)

sourcesQueryOptionalSources to use (if none specified, all sources will be used)

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

All query parameters are case-insensitive.

Note that parameters must be "URL encoded", so a "space-separated list" in a URL 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 interactiondata. It is described in the XML Schema for the Drug Interaction 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 interactiondata. 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:

interactiondata
Root element in XML, or anonymous object in JSON
nlmDisclaimer
userInput
User-provided parameters
sources (array)
Sources of drug interaction information
rxcuis (array)
RxNorm concepts, among which to find interactions
fullInteractionTypeGroup (array)
Interactions from one data source
sourceDisclaimer
sourceName
Source of interaction data (ONCHigh or DrugBank)
fullInteractionType (array)
Two interacting RxNorm concepts and the corresponding interaction-source drugs
comment
minConcept (array)
RxNorm concept
rxcui
RxNorm identifier
name
RxNorm concept name
tty
RxNorm concept's term type
interactionPair (array)
Two interactionConcepts
interactionConcept (array)
RxNorm concept and corresponding drug from an interaction-source data set
minConceptItem
RxNorm concept
rxcui
RxNorm identifier
name
RxNorm concept name
tty
RxNorm concept's term type
sourceConceptItem
Drug from the interaction source's data
id
Source's identifier for the drug
name
Source's name for the drug
url
Location of information from the source of interaction data
severity
Severity (if provided by the source)
description

Example: Diflucan, Zocor, and bosentan oral tablets

XML: https://rxnav.nlm.nih.gov/REST/interaction/list?rxcuis=207106+152923+656659

JSON: https://rxnav.nlm.nih.gov/REST/interaction/list.json?rxcuis=207106+152923+656659

In this example, the interactions between Diflucan 50 mg oral tablet (RxCUI=207106), Zocor 40 mg oral tablet (RxCUI=152923) and bosentan 125 mg oral tablet (RxCUI=656659) are returned.

The result indicates two interactions among the three drugs in the list:

  • Zocor 40 mg oral tablet (RxCUI=152923) with Diflucan 50 mg oral tablet (RxCUI=207106)

  • Zocor 40 mg oral tablet (RxCUI=152923) with bosentan 125 mg oral tablet (RxCUI=656659)

An XML result is shown below.

<interactiondata>
    <nlmDisclaimer>It is not the intention of NLM to provide specific medical advice, but rather to provide users with information to better understand their health and their medications. NLM urges you to consult with a qualified physician for advice about medications.</nlmDisclaimer>
    <userInput>
        ...
    </userInput>
    <fullInteractionTypeGroup>
        <sourceDisclaimer>DrugBank is intended for educational and scientific research purposes only and you expressly acknowledge and agree that use of DrugBank is at your sole risk. The accuracy of DrugBank information is not guaranteed and reliance on DrugBank shall be at your sole risk. DrugBank is not intended as a substitute for professional medical advice, diagnosis or treatment..[www.drugbank.ca]</sourceDisclaimer>
        <sourceName>DrugBank</sourceName>
        <fullInteractionType>
            <comment>Drug1 (rxcui = 207106, name = fluconazole 50 MG Oral Tablet [Diflucan], tty = SBD). Drug2 (rxcui = 656659, name = bosentan 125 MG Oral Tablet, tty = SCD). Drug1 is resolved to fluconazole, Drug2 is resolved to bosentan and interaction asserted in DrugBank between Fluconazole and Bosentan. Drug1 is resolved to fluconazole, Drug2 is resolved to bosentan anhydrous and interaction asserted in DrugBank between Fluconazole and Bosentan.</comment>
            <minConcept>
                <rxcui>207106</rxcui>
                <name>fluconazole 50 MG Oral Tablet [Diflucan]</name>
                <tty>SBD</tty>
            </minConcept>
            <minConcept>
                <rxcui>656659</rxcui>
                <name>bosentan 125 MG Oral Tablet</name>
                <tty>SCD</tty>
            </minConcept>
            <interactionPair>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>4450</rxcui>
                        <name>fluconazole</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00196</id>
                        <name>Fluconazole</name>
                        <url>http://www.drugbank.ca/drugs/DB00196#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>75207</rxcui>
                        <name>bosentan</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00559</id>
                        <name>Bosentan</name>
                        <url>http://www.drugbank.ca/drugs/DB00559#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <severity>N/A</severity>
                <description>The metabolism of Bosentan can be decreased when combined with Fluconazole.</description>
            </interactionPair>
            <interactionPair>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>4450</rxcui>
                        <name>fluconazole</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00196</id>
                        <name>Fluconazole</name>
                        <url>http://www.drugbank.ca/drugs/DB00196#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>1468845</rxcui>
                        <name>bosentan anhydrous</name>
                        <tty>PIN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00559</id>
                        <name>Bosentan</name>
                        <url>http://www.drugbank.ca/drugs/DB00559#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <severity>N/A</severity>
                <description>The metabolism of Bosentan can be decreased when combined with Fluconazole.</description>
            </interactionPair>
        </fullInteractionType>
        <fullInteractionType>
            <comment>Drug1 (rxcui = 152923, name = simvastatin 40 MG Oral Tablet [Zocor], tty = SBD). Drug2 (rxcui = 656659, name = bosentan 125 MG Oral Tablet, tty = SCD). Drug1 is resolved to simvastatin, Drug2 is resolved to bosentan and interaction asserted in DrugBank between Simvastatin and Bosentan. Drug1 is resolved to simvastatin, Drug2 is resolved to bosentan anhydrous and interaction asserted in DrugBank between Simvastatin and Bosentan.</comment>
            <minConcept>
                <rxcui>152923</rxcui>
                <name>simvastatin 40 MG Oral Tablet [Zocor]</name>
                <tty>SBD</tty>
            </minConcept>
            <minConcept>
                <rxcui>656659</rxcui>
                <name>bosentan 125 MG Oral Tablet</name>
                <tty>SCD</tty>
            </minConcept>
            <interactionPair>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>36567</rxcui>
                        <name>simvastatin</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00641</id>
                        <name>Simvastatin</name>
                        <url>http://www.drugbank.ca/drugs/DB00641#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>75207</rxcui>
                        <name>bosentan</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00559</id>
                        <name>Bosentan</name>
                        <url>http://www.drugbank.ca/drugs/DB00559#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <severity>N/A</severity>
                <description>The serum concentration of Simvastatin can be decreased when it is combined with Bosentan.</description>
            </interactionPair>
            <interactionPair>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>36567</rxcui>
                        <name>simvastatin</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00641</id>
                        <name>Simvastatin</name>
                        <url>http://www.drugbank.ca/drugs/DB00641#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>1468845</rxcui>
                        <name>bosentan anhydrous</name>
                        <tty>PIN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00559</id>
                        <name>Bosentan</name>
                        <url>http://www.drugbank.ca/drugs/DB00559#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <severity>N/A</severity>
                <description>The serum concentration of Simvastatin can be decreased when it is combined with Bosentan.</description>
            </interactionPair>
        </fullInteractionType>
        <fullInteractionType>
            <comment>Drug1 (rxcui = 207106, name = fluconazole 50 MG Oral Tablet [Diflucan], tty = SBD). Drug2 (rxcui = 152923, name = simvastatin 40 MG Oral Tablet [Zocor], tty = SBD). Drug1 is resolved to fluconazole, Drug2 is resolved to simvastatin and interaction asserted in DrugBank between Fluconazole and Simvastatin.</comment>
            <minConcept>
                <rxcui>207106</rxcui>
                <name>fluconazole 50 MG Oral Tablet [Diflucan]</name>
                <tty>SBD</tty>
            </minConcept>
            <minConcept>
                <rxcui>152923</rxcui>
                <name>simvastatin 40 MG Oral Tablet [Zocor]</name>
                <tty>SBD</tty>
            </minConcept>
            <interactionPair>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>4450</rxcui>
                        <name>fluconazole</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00196</id>
                        <name>Fluconazole</name>
                        <url>http://www.drugbank.ca/drugs/DB00196#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>36567</rxcui>
                        <name>simvastatin</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>DB00641</id>
                        <name>Simvastatin</name>
                        <url>http://www.drugbank.ca/drugs/DB00641#interactions</url>
                    </sourceConceptItem>
                </interactionConcept>
                <severity>N/A</severity>
                <description>The metabolism of Simvastatin can be decreased when combined with Fluconazole.</description>
            </interactionPair>
        </fullInteractionType>
    </fullInteractionTypeGroup>
    <fullInteractionTypeGroup>
        <sourceDisclaimer>https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3422823/</sourceDisclaimer>
        <sourceName>ONCHigh</sourceName>
        <fullInteractionType>
            <comment>Drug1 (rxcui = 207106, name = fluconazole 50 MG Oral Tablet [Diflucan], tty = SBD). Drug2 (rxcui = 152923, name = simvastatin 40 MG Oral Tablet [Zocor], tty = SBD). Drug1 is resolved to fluconazole, Drug2 is resolved to simvastatin and interaction asserted in ONCHigh between fluconazole and simvastatin.</comment>
            <minConcept>
                <rxcui>207106</rxcui>
                <name>fluconazole 50 MG Oral Tablet [Diflucan]</name>
                <tty>SBD</tty>
            </minConcept>
            <minConcept>
                <rxcui>152923</rxcui>
                <name>simvastatin 40 MG Oral Tablet [Zocor]</name>
                <tty>SBD</tty>
            </minConcept>
            <interactionPair>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>4450</rxcui>
                        <name>fluconazole</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>NA</id>
                        <name>fluconazole</name>
                        <url>NA</url>
                    </sourceConceptItem>
                </interactionConcept>
                <interactionConcept>
                    <minConceptItem>
                        <rxcui>36567</rxcui>
                        <name>simvastatin</name>
                        <tty>IN</tty>
                    </minConceptItem>
                    <sourceConceptItem>
                        <id>NA</id>
                        <name>simvastatin</name>
                        <url>NA</url>
                    </sourceConceptItem>
                </interactionConcept>
                <severity>high</severity>
                <description>HMG Co-A reductase inhibitors - CYP3A4 inhibitors</description>
            </interactionPair>
        </fullInteractionType>
    </fullInteractionTypeGroup>
</interactiondata>