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A service of the U.S. National Library of Medicine
From the National Institutes of HealthNational Institutes of Health

MedlinePlus Connect: Web Application

MedlinePlus Connect is available as a Web application or Web service. Below are the technical details for implementing the Web service, which responds to requests based on:

If you decide to use MedlinePlus Connect, sign up for the email list to keep up with developments and exchange ideas with your colleagues. Please tell us if you implement MedlinePlus Connect by contacting us. You are welcome to link to and display the data provided by MedlinePlus Connect. For more information on how to link to MedlinePlus content outside of this service, please see our guidelines and instructions on linking.

Web Application Overview

The API for the Web application conforms to the HL7 Context-Aware Knowledge Retrieval (Infobutton) Knowledge Request URL-Based Implementation specification. The structure of the request indicates what type of code you are sending. In all cases, the base URL for the Web application is:

http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm

MedlinePlus Connect works over HTTP or HTTPS.

Requests for Diagnosis (Problem) Codes

MedlinePlus Connect matches ICD-9-CM or SNOMED CT codes to related MedlinePlus topic pages of consumer health information. For example, a patient diagnosed with Asthma, ICD-9-CM code 493.12, could be presented a link in an electronic health record that is called: 493.12 Extrinsic asthma with exacerbation.

If the patient portal or EHR is using MedlinePlus Connect, that text could be linked. Clicking on the link brings the user to a MedlinePlus Connect response page displaying up to three MedlinePlus topic summaries and selected links, if available. From that page, a user may continue to the complete MedlinePlus health topic page, or to any of the individual links on the response page.

For requests by problem, the base URL of the application is:
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm

This link displays a page with an empty search box. There are two required parameters for any query to this application:

  1. Identify the problem code system you will be using, either ICD-9-CM or SNOMED CT. Note: MedlinePlus Connect coverage of SNOMED CT focuses on the CORE Problem List subset codes and their descendants.
    For ICD-9-CM use:
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.103

    MedlinePlus Connect will also accept:
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.2
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.42

    For SNOMED CT use:
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.96

  2. Identify the actual code that you are trying to look up:
    mainSearchCriteria.v.c=250.33

Optional Parameters

Identify the name/title of the problem code. Sending no code will result in a query to the MedlinePlus search engine. If you specify a code and the name/title of the code, but MedlinePlus Connect has no results, the response page will display a MedlinePlus search box prepopulated with the name/title.

mainSearchCriteria.v.dn=Diabetes mellitus with other coma type 1 uncontrolled

Identify if you would like the request to be in English or Spanish. MedlinePlus Connect will assume English is the language if it is not specified.

If you wish the response to the problem code lookup to be in Spanish, use:
informationRecipient.languageCode.c=sp

To specify English, use the following:
informationRecipient.languageCode.c=en

Examples of Requests for Problem Codes

A complete request for Diabetes Mellitus with other coma type 1 uncontrolled, ICD-9 code 250.33, for a Spanish speaking patient would have the following URL address:

http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.103&mainSearchCriteria.v.c=250.33&mainSearchCriteria.v.dn=Diabetes%20mellitus%20with%20other%20coma%20type%201%20uncontrolled&informationRecipient.languageCode.c=sp

A patient diagnosed with "Pneumonia due to Pseudomonas" using SNOMED CT code 41381004:

http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.96&mainSearchCriteria.v.c=41381004&mainSearchCriteria.v.dn=Pneumonia%20due%20to%20Pseudomonas%20%28disorder%29&informationRecipient.languageCode.c=en

A freeform query, with no code system or problem code, will use the MedlinePlus search engine (English only):

http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.dn=Type+2+Diabetes

Requests for Drug Information

MedlinePlus Connect provides the best drug information matches when receiving an RXCUI. It also provides good results when receiving an NDC code. If you do not send an NDC or RXCUI code, the application will use the text string that you send to display the best possible drug information match. If MedlinePlus Connect finds a null response for a drug request, the program displays a search box for the MedlinePlus site. A user can type in a drug name and may get a good response. MedlinePlus Connect returns a link to a search results page with the best matches from the MedlinePlus drug information.

At this time, MedlinePlus Connect provides responses to medication information in English only.

For requests for drug information, the base URL is:
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm

These are the pieces of information you need to send a full request:

  1. Identify the type of medication code you are sending.
    For RXCUI use:
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.88

    For NDC use:
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.69

  2. Identify the actual code you are trying to look up.
    mainSearchCriteria.v.c=637188

  3. Identify the name of the drug with a text string.
    mainSearchCriteria.v.dn=Chantix 0.5 MG Oral Tablet

At a minimum you should identify the code system and the code, or the code system and the name of the drug. All three are preferred. A freeform query, with no code system or medication code, will use the MedlinePlus search engine. This approach is more effective with diagnoses (see the problem code information above) instead of drug name text strings. Your drug information request should look like one of the following.

To request information by an RXCUI, your request should look like this:
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.88&mainSearchCriteria.v.c=%20637188%20&mainSearchCriteria.v.dn=Chantix%200.5%20MG%20Oral%20Tablet
To request information by an NDC, your request should look like this:
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.69&mainSearchCriteria.v.c=%2000310-0751-39&mainSearchCriteria.v.dn=Crestor%2010%20MG%20Oral%20Tablet
To send a Text String without a medication code, you must identify your query as an NDC-type request so MedlinePlus Connect knows you are looking for medication information. Your request could look like this:
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.69&mainSearchCriteria.v.dn=Chantix%200.5%20MG%20Oral%20Tablet

Requests for Lab Test Information

MedlinePlus Connect provides matches to laboratory test information when receiving a LOINC request. MedlinePlus Connect can provide responses to lab test requests in English or Spanish and will return a link to a results page with the best matches from the MedlinePlus lab test information.

For requests for lab test information, the base URL is:
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm

These are two required parameters for any lab test query to this application:

  1. Identify that you are using the LOINC code system.
    For LOINC use:
    mainSearchCriteria.v.cs=2.16.840.1.113883.6.1

    2. MedlinePlus Connect will also accept:
    mainSearchCriteria.v.cs=2.16.840.1.113883.11.79

  2. Identify the actual code you are trying to look up.
    mainSearchCriteria.v.c=3187-2

Optional Parameters

Identify the name/title of the lab test. However, this information does not impact the response.

mainSearchCriteria.v.dn=Factor IX assay

Identify if you would like the request to be in English or Spanish. MedlinePlus Connect will assume English is the language if it is not specified.

If you wish the response to the problem code lookup to be in Spanish, use:
informationRecipient.languageCode.c=sp

To specify English, use the following:
informationRecipient.languageCode.c=en

A freeform query, with no code system or lab code, will use the MedlinePlus search engine. This approach is more effective with diagnoses (see the problem code information above) instead of lab test text strings. Your lab test information request should look like one of the following.

Examples of Requests for Lab Tests

To request information for an English speaker, your request may look like one of the following:

http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.1&mainSearchCriteria.v.c=3187-2&mainSearchCriteria.v.dn=Factor%20IX%20assay&informationRecipient.languageCode.c=en
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.1&mainSearchCriteria.v.c=3187-2&informationRecipient.languageCode.c=en

To request information for a Spanish speaker, your request may look like one of the following:

http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.1&mainSearchCriteria.v.c=3187-2&mainSearchCriteria.v.dn=Factor%20IX%20assay&informationRecipient.languageCode.c=sp
http://apps.nlm.nih.gov/medlineplus/services/mpconnect.cfm?mainSearchCriteria.v.cs=2.16.840.1.113883.6.1&mainSearchCriteria.v.c=3187-2&informationRecipient.languageCode.c=sp

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