FDA Drug Safety Explorer
Search any medication to see real FDA adverse event reports. Side effects ranked by frequency, severity breakdowns, demographic patterns, outcomes, and trends over time. Compare two drugs side by side.
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How the Drug Safety Explorer Works
This tool queries the openFDA Drug Adverse Event API, which provides public access to the FDA Adverse Event Reporting System (FAERS). FAERS contains millions of adverse event reports submitted by healthcare professionals, patients, and pharmaceutical manufacturers since the 1960s. Every search runs against the live API in real time.
When you enter a drug name, the tool sends multiple parallel requests to the openFDA API. It fetches the total report count, the top 25 most frequently reported adverse reactions (coded using the MedDRA medical terminology standard), severity breakdown (serious vs. non-serious), patient sex distribution, age distribution, patient outcomes (recovered, fatal, unknown), and reporting trends over time by year.
The bar charts rank reactions by raw report count, with percentages calculated against the total number of reports for that drug. The donut charts show proportional breakdowns of sex, outcomes, and severity. The timeline chart plots report volume by year so you can spot trends, such as a spike in reports following a new safety warning or a drop after a drug is reformulated.
When you enable comparison mode, the tool fetches the same data for a second drug and overlays both datasets. Reaction bars show both drugs simultaneously, making it simple to see which side effects are more common with one medication versus another. All data is presented without editorial interpretation.
Example: Comparing Metformin and Glipizide Side Effect Profiles
Suppose your doctor mentions switching your diabetes medication from metformin to glipizide and you want to understand the safety data before your next appointment. Type "metformin" in the search bar and click Analyze. The tool shows that metformin has hundreds of thousands of FAERS reports, with the most frequently reported reactions including nausea, diarrhea, and lactic acidosis.
Now check "Compare with another drug" and type "glipizide." The tool loads both profiles side by side. You can see that glipizide has fewer total reports (because fewer people take it), but hypoglycemia appears much higher in its reaction list. The severity donut might show a higher percentage of serious reports for one drug compared to the other.
Bring this data to your doctor's visit. It does not replace clinical judgment, but it gives you an informed starting point for a conversation about which medication profile better fits your health situation. Remember that higher report counts often reflect broader usage, not necessarily higher risk.
What You Can Do With This Tool
The Drug Safety Explorer lets you look up any medication by name and see what adverse events have been reported to the FDA. You can review the 25 most common side effects ranked by frequency, check what percentage of reports are classified as serious, see how outcomes break down (recovered, fatal, not recovered), and examine age and sex demographics of people who filed reports.
The comparison mode is especially useful when evaluating alternatives within the same drug class. You can compare any two medications head to head on reaction frequency, severity distribution, and reporting trends. Every analysis links to the official openFDA data portal and FDA MedWatch for reporting your own experiences.
Frequently Asked Questions
Does a reported adverse event mean the drug caused it?
No. FAERS reports are voluntary submissions that describe events occurring while a patient was taking a medication. The event may have been caused by the drug, another medication, an underlying condition, or something unrelated entirely. A report documents a temporal association, not a confirmed causal link.
Why does aspirin have more reports than a newer drug?
Report volume correlates strongly with how many people take a drug and how long it has been on the market. A medication prescribed to 100 million people will naturally accumulate more reports than one prescribed to 500,000 people, even if the newer drug has a higher per-patient event rate. Never compare raw counts between drugs without considering usage volume.
What does "serious" mean in the severity breakdown?
The FDA classifies a report as "serious" if the event resulted in death, a life-threatening situation, hospitalization, disability, a congenital anomaly, or required medical intervention to prevent one of these outcomes. Non-serious reports cover events that did not meet any of those thresholds.
How often is the FAERS data updated?
The openFDA API updates its adverse event data quarterly, typically reflecting reports received through the end of the previous quarter. There is usually a 3-to-6 month lag between when a report is submitted to MedWatch and when it appears in the public API.
Can I use this to decide whether to stop taking a medication?
Absolutely not. This tool shows raw reporting data for educational purposes. It is not a substitute for medical advice. Never stop, start, or change a medication based on FAERS data alone. Discuss any concerns with your prescribing physician or pharmacist, who can evaluate your individual health situation.
What is MedDRA and why are reaction names sometimes confusing?
Reactions in FAERS are coded using the Medical Dictionary for Regulatory Activities (MedDRA), a standardized terminology used worldwide for regulatory reporting. Terms like "pyrexia" (fever) or "dyspnoea" (shortness of breath) are standard medical vocabulary. The tool displays these terms as they appear in the API. You can search any unfamiliar term on MedlinePlus for a plain-language explanation.
Data Sources and Methodology
All data is sourced from the openFDA Drug Adverse Event API, maintained by the U.S. Food and Drug Administration. The underlying dataset is the FDA Adverse Event Reporting System (FAERS), which collects voluntary reports of adverse events and medication errors submitted by healthcare professionals, consumers, and manufacturers.
Reaction terms use the MedDRA (Medical Dictionary for Regulatory Activities) coding system. Patient demographics, outcomes, and severity classifications follow FDA FAERS field definitions. Report counts, percentages, and timeline aggregations are computed client-side from the raw API response. No data is filtered, modified, or editorially weighted.