clonazepam Side Effects
Also known as: Klonopin
Analysis of 155,147 adverse event reports submitted to the FDA from 2002 to 2025.
Total Reports
155,147
Death-Related
18,179
11.7% of reports
Hospitalizations
46,031
29.7% of reports
Top Indication
Product Used For Unknown Indication
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 18,179 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| COMPLETED SUICIDE | 4,873 |
| DEATH | 4,159 |
| TOXICITY TO VARIOUS AGENTS | 3,552 |
| CARDIAC ARREST | 1,504 |
| DRUG ABUSE | 1,409 |
| CARDIO-RESPIRATORY ARREST | 1,405 |
| RESPIRATORY ARREST | 1,092 |
| OVERDOSE | 969 |
| DRUG INTERACTION | 651 |
| PNEUMONIA | 592 |
| DEPRESSION | 502 |
| OFF LABEL USE | 443 |
| POISONING | 394 |
| PULMONARY OEDEMA | 377 |
| RESPIRATORY FAILURE | 371 |
| DYSPNOEA | 369 |
| HYPOTENSION | 363 |
| FALL | 352 |
| DRUG DEPENDENCE | 344 |
| UNRESPONSIVE TO STIMULI | 326 |
Reactions in Hospitalization Reports
Top reactions in 46,031 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| FALL | 3,372 |
| PNEUMONIA | 3,043 |
| ANXIETY | 3,014 |
| NAUSEA | 2,962 |
| DRUG INEFFECTIVE | 2,891 |
| DEPRESSION | 2,820 |
| DYSPNOEA | 2,787 |
| FATIGUE | 2,745 |
| PAIN | 2,701 |
| VOMITING | 2,676 |
| OFF LABEL USE | 2,533 |
| HEADACHE | 2,446 |
| DIARRHOEA | 2,330 |
| DIZZINESS | 2,124 |
| ASTHENIA | 2,095 |
| PYREXIA | 2,078 |
| DRUG INTERACTION | 2,015 |
| MALAISE | 1,974 |
| INSOMNIA | 1,891 |
| TOXICITY TO VARIOUS AGENTS | 1,838 |
Nearby — Related Medications
What the FAERS Data Reveals About clonazepam Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 155,147 voluntary reports linked to clonazepam and its brand equivalents (Klonopin), spanning 2002 through 2025. Of those, 18,179 (11.7%) listed death as an outcome and 46,031 (29.7%) involved hospitalization. The most common indication reported alongside adverse events was Product Used For Unknown Indication.
Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 65% were female and 35% male; age distribution skews toward 45-64, with 42,428 reports in that bracket. The single most reported reaction is drug ineffective with 13,608 submissions, followed by fatigue and nausea.
FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice — speak with a licensed clinician about any side-effect concerns.
Read our methodology — how this data is sourced, computed, and verified.