For search queries (such as: https://api.fda.gov/other/substance.json?search=definition_type:"PRIMARY"), the results section includes matching adverse event reports returned by the API.
Each substance result consists of these major sections:
Substance:The top level fields of each record.Codes:A list of codes used for this record, containing external identifiers, external classification designations, and external link-outs.Mixture:A container for the mixture information necessary to define a mixture substance. This includes the mixture components and an optioanl source material reference.Modifications:A container for the set of physical, structural and agent modifications on the substance record.Moieties:A list of the important component chemical structures which comprise a chemical substance, as well as their relative ratios to each other (especially important in the case of non-stoichiometric chemical substances). These "moieties" are typically the unique set of disconnected covalent structures found in the substance.Names:The list of names associated with a record. These include scientific, common, generic and brand names for substances and concepts. Name objects include both the name as a string, as well as other information.Notes:A list of notes and general comments for the record.Nucleic Acid:The definitional information of a nucleic acid substance. Contains information about the nucleic acid sequence as well as the sugars and linkages used.Polymer:The definitional information of a polymer substance. Contains information about the monomers, structural repeat units, amounts, connectivity and idealized structural form of the polymer.Protein:The definitional information of a protein substance. Contains information about the amino acid sequence, gylcosylation, classification, disulfide links and other links.References:A list of reference uuids, which refer back to the root record's references, essentially acting as footnotes.Relationships:A list of related records which share some known relationship with this record (e.g. salt forms, metabolites, impurities, etc).Structurally Diverse:The definitional information of a structurally diverse substance. This includes information about the source of the material (e.g. taxonomy for organisms) as well as the state, form and part of the source material used.Structure:Chemical structure of a chemical substance.For count queries (such as: https://api.fda.gov/other/substance.json?count=substance_class), the results section will look something like the following:
[
{
"term": "chemical",
"count": 72108
},
{
"term": "structurallyDiverse",
"count": 25508
},
{
"term": "protein",
"count": 4175
},
{
"term": "mixture",
"count": 2508
},
{
"term": "polymer",
"count": 2128
},
{
"term": "concept",
"count": 713
},
{
"term": "nucleicAcid",
"count": 190
},
{
"term": "specifiedSubstanceG1",
"count": 23
}
]