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Pharmacological Actions. Documentation.

1. Introduction

A special file of Pharmacological Action (PA) data is available in XML format. The file is independent of other MeSH files in XML format but uses some of the same techniques for representing data, such as referring to Descriptors by the element <DescriptorReferredTo> and its sub-elements, so users may find it helpful to consult Introduction to XML MeSH.

The file consists of mappings between Pharmacological Action Descriptors, on the one hand, and substances having a particular action, on the other. Substances include both Descriptor records and Supplementary Concept Records (SCRs). These mappings include the PA data in the full XML files but also include as <PharmacologicalAction> selected Descriptors which are ancestors of a PA in the MeSH Tree hierarchy. These ancestors may be other PAs or Descriptors which may be too broad to be associated with a specific substance, but useful for grouping a larger set of substances.

For example, the substance Albuterol has the PA Bronchodilator Agents in the full MeSH files.

Substance = Albuterol
PA = Bronchodilator Agents

A broader Descriptor of the PA is Autonomic Agents, though not a PA itself.

Ancestor of PA = Autonomic Agents
PA = Bronchodilator Agents
Substance = Albuterol

It is desirable to treat the Autonomic Agents as a PA for retrieval purposes so this Descriptor included in the PA file as a <PharmacologicalAction> of Albuterol.

2. File structure

The file is a list of Pharmacological Actions with corresponding substances.

Pharmacological Action Substance
Antacids Aluminum Hydroxide
  aluminum phosphate

3. XML elements:

Element Name Description
<DescriptorName> Name (= preferred term) of the Pharmacological Action (PA) Descriptor.
<DescriptorReferredTo> The pair consisting in both the name and UI of the PA Descriptor.
<DescriptorUI> Seven-digit Unique Identifier of the PA Descriptor.
<PharmacologicalActionSubstanceList> The list of all substances under a given PA.
<PharmacologicalAction> A given Pharmacological Action (PA) Descriptor.
<PharmacologicalActionSet> The parent element of the entire XML file of PAs.
<RecordName> Name (= preferred term) of the substance record.
<RecordUI> Unique Identifier of the substance record.
<String> The character string comprising the PA name and substance name.
<Substance> The pair consisting in both the name and UI of the substance record.

4. Availability

The file is updated weekly, primarily to include changes in the SCR PAs which may change during the year.

Through 2007 a second PA file was available - a listing by substance. However, the file was redundant since the data may be extracted from the full Descriptor XML file.

Access the XML file of Substances with a given Pharmacological Action via the Download MeSH Data page.

For more information, see Searching Drugs or Chemicals in PubMed and PubMed and the Expansion of Pharmacological Action Terms.

5. Contact

For questions, concerns, or to provide feedback, please visit the NLM Support Center.

Last Reviewed: October 19, 2021