Methodology & Data Sources

How we collect, process, and present medication information.

Data Sources

Every piece of information on PlainMeds comes from official, publicly available FDA and CMS databases, all retrieved via the openFDA API at open.fda.gov, FDA bulk download services, and the CMS Medicaid open data portal:

  • FDA Drug Labels (SPL, Structured Product Labeling): The full official labeling that pharmaceutical manufacturers submit to the FDA. This is the same information your pharmacist reads, covering indications, dosage, warnings, contraindications, drug interactions, and adverse reactions. Source: FDA Structured Product Labeling Resources + NLM DailyMed. Our drug interaction data is derived from these same labels.
  • FDA Adverse Event Reporting System (FAERS): Real-world reports of adverse events submitted by healthcare professionals, patients, and manufacturers. We use aggregated FAERS data to show which side effects are reported most frequently in post-market surveillance. Source: FDA FAERS Public Dashboard.
  • FDA Drug Shortage Database: Active drug shortages self-reported by manufacturers under FDA reporting requirements. Source: FDA Drug Shortage Database.
  • CMS National Average Drug Acquisition Cost (NADAC): The average wholesale price pharmacies pay to acquire a medication, published weekly by CMS. Powers our drug-cost comparison pages. Source: CMS/Medicaid Open Data Portal.
  • FDA Orange Book & NDC Directory: Approved drug products, therapeutic equivalence ratings, and patent/exclusivity data used for our generic-vs-brand comparisons. Source: FDA Orange Book + FDA NDC Directory.
  • FDA Drug Enforcement Reports: Official recall and enforcement actions from the FDA. We track active recalls so users can check whether any of their medications have been affected. Source: FDA Recalls, Market Withdrawals, & Safety Alerts.

Processing Pipeline

We download FDA drug label data from the openFDA API and bulk data files. Our ETL pipeline:

  • Extracts structured sections from SPL XML files (warnings, indications, dosage, interactions)
  • Applies editorial plain-language simplification to translate complex medical language into plain English
  • Joins drug records with FAERS adverse event counts by application number
  • Links active recall records to drug entries where matching brand or generic names are found
  • Indexes all drugs by brand name, generic name, and active ingredient for search

Two kinds of text sit on a drug page, and it matters which is which. Quoted material reproduces the FDA label exactly: the interaction text, the adverse-event counts, and the recall records. The narrative sections, including the summary, what it treats, how to take it, side effects, warnings and pregnancy notes, are rewritten in plain English from that label and are therefore our wording, not the label's. Read them as a way in; the label itself, and your prescriber or pharmacist, remain the authority on dosing and warnings.

FAERS Data Interpretation

FAERS adverse event reports are submitted voluntarily and represent reports received by the FDA, not confirmed causal relationships. The presence of a drug in FAERS reports does not mean the drug caused the reported event. FAERS data is used for hypothesis generation and signal detection, not to establish drug safety conclusions. Reporting rates may be influenced by media attention, drug popularity, and healthcare professional awareness.

Data Vintage and Update Frequency

FDA drug label data is updated continuously as manufacturers submit new or revised Structured Product Labeling to the FDA. The openFDA API reflects these submissions with minimal delay. FAERS adverse event data is published quarterly by the FDA, with each release covering the most recent complete quarter. Drug enforcement and recall data is updated as the FDA issues new enforcement actions. PlainMeds refreshes its database periodically to incorporate new drug labels, updated FAERS data, and current recall status.

Accuracy Commitment

The structured data on this site is reproduced from its FDA source unchanged: drug interaction text is quoted from the labels, adverse-event figures are the FAERS report counts, and recall records are the enforcement entries as published. The narrative sections of a drug page are rewritten from the label rather than quoted from it, so their wording is ours and can differ from the official text in emphasis or detail even where the substance is the same. That is why every drug page links the source label, and why a rewritten warning should never be treated as the operative one. When label data is unavailable or incomplete for a medication, we display that rather than estimate it.

Corpus placement (#N of M)

Entity pages state where each record sits in PlainMeds's own corpus - a computed rank among peers with the same honest filter, not a restyled FDA field. Bases:

  • Drugs - FAERS total report volume descending among drugs with FAERS summaries and total_reports greater than zero. Volume reflects reporting and use, not proven danger.
  • Categories - drug inventory count descending among therapeutic classes with at least 3 tracked drugs.
  • Shortages - days since initial FDA posting among Current shortages with parseable MM/DD/YYYY dates, ranked per drug slug (matches the longest-shortages leaderboard predicate).

Ties break on stable slug order so ranks are reproducible on rebuild. Placement text links here so readers can verify the basis.

Limitations

  • Drug label information may not reflect the most recent label revision if the manufacturer's updated SPL has not yet been processed by the FDA or the openFDA system. Always consult your pharmacist or prescriber for current prescribing information.
  • FAERS counts reflect reports received by the FDA, not the rate of adverse events per population of users. More widely prescribed medications will naturally accumulate more reports, regardless of their actual safety profile.
  • Our plain-language summaries are aids to understanding complex medical language, not substitutes for professional medical advice or the full official drug label.
  • Not all medications available on the US market are in the FDA SPL database. Some older drugs, compounded medications, and over-the-counter products may not appear or may have limited label data.
  • PlainMeds is not affiliated with the FDA or any government agency.

Important Disclaimer

This site is for informational purposes only and does not provide medical advice. Nothing on PlainMeds constitutes a recommendation to use, discontinue, or alter any medication. Always consult your doctor, pharmacist, or qualified healthcare provider before making any decisions about your medications.