api.fda.gov/drug/event
An adverse event is submitted to the FDA to report any undesirable experience associated with the use of a drug, including serious drug side effects, product use errors, product quality problems, and therapeutic failures.
About drug adverse events
The U.S. Food and Drug Administration (FDA) regulates over-the-counter and prescription drugs in the United States, including biological therapeutics and generic drugs. This work covers more than just medicines. For example, fluoride toothpaste, antiperspirants, dandruff shampoos and sunscreens are all considered drugs.
An adverse event is submitted to the FDA to report any undesirable experience associated with the use of a medical product in a patient. For drugs, this includes serious drug side effects, product use errors, product quality problems, and therapeutic failures for prescription or over-the-counter medicines and medicines administered to hospital patients or at outpatient infusion centers.
Adverse event reports
This highly simplified schematic illustrates the general nature of an adverse event report. A report may list several drug products, as well as several patient reactions. No individual drug is connected to any individual reaction. When a report lists multiple drugs and multiple reactions, there is no way to conclude from the data therein that a given drug is responsible for a given reaction.
- Product A
- Product B
- Product C
- Product D
- Product E
- Reaction 1
- Reaction 2
- Reaction 3
Any number of the drugs may be marked as suspect if thought to be responsible for one or more of the reactions, but that information is not validated. Concomitant drugs are those which are not suspected of causing one or more of the reactions. Many drug products appear frequently in adverse event reports simply because they are commonly taken by many people in the population, not because they are responsible for more adverse events.
Reports contain varying levels of detail about the drug products involved, indications for use, route of administration, and dose.
Get your API key
We require API keys above a certain number of requests to manage load on the system, promote equitable access, and prevent abuse. See more about how to use your API key.
Signing up for an API key means you agree to our terms of service.
How to search this endpoint
Make API calls to https://api.fda.gov/drug/event.json using search parameters for fields specific to the drug adverse events endpoint.
Example API query
One adverse event report
This query searches for all records in a certain date range, and asks for a single one. See the header fields reference for more about receivedate. Brackets [ ] are used to specify a range for date, number, or string fields.
See the header fields reference for more about receivedate. Brackets [ ] are used to specify a range for date, number, or string fields.
search for all records with receivedate between Jan 01, 2004 and Dec 31, 2008. limit to 1 record.
see the header fields reference for more about receivedate. Brackets [ ] are used to specify a range for date, number, or string fields.
Example API query
One adverse event report with a drug from a certain pharmacologic class
This query searches records listing a drug of a certain pharmacologic class, and returns a single record. A record returned by this query may have multiple drugs listed. At least one of the drugs belongs to the pharmacologic class. See the openFDA fields reference for more about the kinds of searches they enable. Double quotation marks " " surround phrases that must match exactly. The plus sign + is used in place of a space character .
A record returned by this query may have multiple drugs listed. At least one of the drugs belongs to the pharmacologic class. See the openFDA fields reference for more about the kinds of searches they enable.
Double quotation marks " " surround phrases that must match exactly. The plus sign + is used in place of a space character.
search for all records with receivedate between Jan 01, 2004 and Dec 31, 2008. limit to 1 record.
see the header fields reference for more about receivedate. Brackets [ ] are used to specify a range for date, number, or string fields.
Example API query
Count of patient reactions
This query is similar to the prior one, but returns a count of the 1000 most frequently reported patient reactions. Multiple drugs in the records may match this class, and the drugs from this class may not be those which caused the associated adverse patient reactions. The suffix .exact is required by openFDA to count the unique full phrases in the field patient.reaction.reactionmeddrapt. Without it, the API will count each word in that field individually—difficulty sleeping would be counted as separate values, difficulty and sleeping. See the patient reaction reference for more about patient reactions in adverse event records.
The suffix .exact is required by openFDA to count the unique full phrases in the field patient.reaction.reactionmeddrapt. Without it, the API will count each word in that field individually—difficulty sleeping would be counted as separate values, difficulty and sleeping.
See the patient reaction reference for more about patient reactions in adverse event records.
search for all records with receivedate between Jan 01, 2004 and Dec 31, 2008. limit to 1 record.
see the header fields reference for more about receivedate. Brackets
[ ]are used to specify a range for date, number, or string fields.