query drug adverse-event data from the openFDA API

Steps

1. Send a GET request to https://api.fda.gov/drug/event.json with a search parameter using Lucene query syntax, e.g. search=patient.drug.medicinalproduct:aspirin to find adverse event reports mentioning a drug.
2. Use limit (max 1000 per request) and skip for pagination; for large result sets, iterate using skip offsets up to the total count returned in meta.results.total.
3. To aggregate counts by reaction, use the count endpoint: https://api.fda.gov/drug/event.json?search=...&count=patient.reaction.reactionmeddrapt.exact to get a frequency breakdown by MedDRA preferred term.
4. Apply an API key (obtained free from https://open.fda.gov/apis/authentication/) to get higher rate limits (240 requests/minute vs 40 without a key); include it as the api_key query parameter.
5. Filter by seriousness flags (e.g. serious:1, seriousnesslifethreatening:1) to focus on clinically significant reports.
6. Supplement openFDA data with results.safetyreportid and results.reportduplicate fields to identify and exclude duplicate reports when doing quantitative analysis.