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Pharmacologic Action [pa] (continued)

To search for a specific action of a substance, use the [mh] search tag with the pharmacological action.


aspirin [mh] AND platelet aggregation inhibitors [mh]

To search all substances assigned a particular pharmacological action, use the [pa] field tag.


caustics [pa] AND skin [mh]

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The video illustrates the directions that are on this page.

This video can be seen directly at //www.nlm.nih.gov/bsd/disted/pubmedtutorial/videos/pm_tutorial_020_750.mp4

Use of a term with the Pharmacologic Action [pa] field tag instructs PubMed to OR together terms from a list made up of a PA term and the drug/substance terms known to have that action. Use the MeSH Database to display the substances known to have a particular pharmacologic action.

Any MeSH terms on the list are searched with the no explode specification, [mh:noexp], so as not to include possible indentions of the term that might not share the pharmacologic action.

Note: If you enter a MeSH term that happens to be a PA term, without using a field tag, PubMed will search the term as [mh], [pa], and [All Fields].

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Last Reviewed: August 27, 2018