Reported Reactions

Drugs › Benzodiazepine

Generic name

Clonazepam: adverse event reports filed with FDA

37,432 reports list it as a suspect or interacting product, 2004–2026. Class: Benzodiazepine. Also reported as Clonazepam Tablets Usp, Clonazepam 1mg, Clonazepam 0 5mg.

37,432
reports as suspect product
0.2% of all reports · about 1,664 a year
2,530
reports, 12 months to June 2026
2,613 in the 12 months before
86.7%
marked serious by the reporter
88.1% across the class
29.9%
record death among outcomes, as reported
11,185 reports · not verified by FDA

Between January 2004 and June 2026, 37,432 adverse event reports received by FDA list clonazepam, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (82,253) are left out of every figure here.

In the 12 months to June 2026, 2,530 reports listed it, close to the 2,613 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 1,664 reports a year and 0.2% of the 20,646,523 reports in the database, and 15.3% of the reports for the benzodiazepine class. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are completed suicide (12.8%), toxicity to various agents (11.9%) and drug ineffective (11.5%). A report can list several reactions, so shares add to more than 100%; 2,636 different terms appear across these reports. Completed suicide is recorded in 12.8% of these reports, a larger share than in the median benzodiazepine drug (1.7%).

86.7% of the reports are marked serious by the reporter (88.1% across the class); 29.9% record death among the outcomes and 31.9% record hospitalisation, as reported. 35.1% of the reports came from other health professionals, and the largest patient age group is 18 to 44 (30.7%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

0194388Jul 2021: 303Aug 2021: 253Sep 2021: 264Oct 2021: 257Nov 2021: 193Dec 2021: 2842022Jan 2022: 277Feb 2022: 310Mar 2022: 388Apr 2022: 245May 2022: 208Jun 2022: 313Jul 2022: 239Aug 2022: 228Sep 2022: 220Oct 2022: 232Nov 2022: 267Dec 2022: 2252023Jan 2023: 313Feb 2023: 362Mar 2023: 188Apr 2023: 234May 2023: 236Jun 2023: 343Jul 2023: 282Aug 2023: 176Sep 2023: 138Oct 2023: 176Nov 2023: 191Dec 2023: 1742024Jan 2024: 242Feb 2024: 180Mar 2024: 222Apr 2024: 273May 2024: 230Jun 2024: 199Jul 2024: 199Aug 2024: 304Sep 2024: 242Oct 2024: 245Nov 2024: 284Dec 2024: 2142025Jan 2025: 225Feb 2025: 225Mar 2025: 191Apr 2025: 160May 2025: 129Jun 2025: 195Jul 2025: 230Aug 2025: 183Sep 2025: 185Oct 2025: 178Nov 2025: 252Dec 2025: 1772026Jan 2026: 215Feb 2026: 236Mar 2026: 187Apr 2026: 237May 2026: 250Jun 2026: 200

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

01,6173,2332004: 20720042005: 4082006: 2792007: 30820072008: 5852009: 5232010: 63620102011: 9672012: 1,0592013: 1,08820132014: 1,5552015: 1,7742016: 1,38820162017: 2,3102018: 2,5622019: 2,93520192020: 3,2332021: 3,1612022: 3,15220222023: 2,8132024: 2,8342025: 2,33020252026: 1,325

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Clonazepam reports recording the termmedian drug in benzodiazepine

  1. Completed suicidedeath by suicide12.8%4,785
  2. Toxicity to various agentspoisoning or toxic effect of one or more substances11.9%4,451
  3. Drug ineffectivethe medicine did not work as expected11.5%4,293
  4. Drug abusemisuse of a medicine7.1%2,671
  5. Drug interactionan interaction between medicines7%2,623
  6. Off label useused for a purpose or in a way not on the label5.9%2,208
  7. Depressionlow mood5.4%2,035
  8. Dyspnoeashortness of breath5.4%2,020
  9. Anxietyanxiety5.1%1,915
  10. Vomitingbeing sick5%1,858
  11. Somnolencedrowsiness4.9%1,826
  12. Pneumonialung infection4.8%1,798
  13. Overdosea dose above the recommended amount4.1%1,522
  14. Asthmaasthma4%1,491
  15. Fatiguetiredness3.9%1,477
  16. Malaisegeneral feeling of being unwell3.9%1,456
  17. Deaththe patient died; cause not stated by this term3.9%1,442
  18. Headachehead pain3.7%1,402
  19. Cardiac arrestthe heart stopped3.6%1,355
  20. Painpain, site not specified3.6%1,354
  21. Cardio-respiratory arrestthe heart and breathing stopped3.6%1,347
  22. Wheezingwheezing3.5%1,310
  23. Insomniadifficulty sleeping3.5%1,305
  24. Nauseafeeling sick3.3%1,249
  25. Drug hypersensitivityan allergic-type reaction to a medicine3.3%1,248
  26. Intentional overdosea deliberate overdose3.2%1,184
  27. Suicide attempta suicide attempt3.1%1,166
  28. Dizzinesslight-headedness or unsteadiness3.1%1,145
  29. Respiratory arrestbreathing stopped2.9%1,091
  30. Product use in unapproved indicationused for a purpose not on the label2.8%1,052

Top 30 of 2,636 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 19 drugs in the benzodiazepine class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death29.9%11,185
Life-threatening6.8%2,536
Hospitalisation (initial or prolonged)31.9%11,927
Disability2.2%837
Congenital anomaly1%378
Other serious50.2%18,807
Not serious13.3%4,994

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 244,289 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 21%385
2 to 111.8%663
12 to 172.6%978
18 to 4430.7%11,479
45 to 6426.4%9,898
65 to 748.2%3,054
75 and over3.9%1,472
Age not given25.4%9,503

Patient sex

Female50.8%19,003
Male38.8%14,524
Not given10.4%3,905

Who reported

Physician29.5%11,046
Pharmacist8.9%3,323
Other health professional35.1%13,137
Lawyer0.2%75
Consumer or non-health professional23.4%8,744
Not given3%1,107

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 50.8% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Anxiety1,9875.3%
Epilepsy9032.4%
Seizure6941.9%
Bipolar disorder6911.8%
Insomnia5831.6%
Depression5691.5%

The indication field is filled in by the reporter and is often blank; shares are of all 37,432 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Clonazepam reports
Quetiapine3,73810%
Gabapentin3,0038%
Diazepam2,8197.5%
Valproic acid2,5686.9%
Lamotrigine2,4676.6%
Pregabalin2,3366.2%
Acetaminophen2,2516%
Levetiracetam2,2506%
Trazodone2,1075.6%
Lorazepam2,0975.6%

Other products listed in reports where Clonazepam is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureClonazepamBenzodiazepineAll reports
Reports as suspect product37,432244,28920,646,523
Share of that pool—15.3%0.2%
Reports, latest 12 months2,530—1,332,454
Marked serious86.7%88.1%57.4%
Death recorded among outcomes, per 1,000 reports29929791
Hospitalisation recorded, per 1,000 reports319346213
Consumer-filed share23.4%21.3%45.8%
Top term, share of reportsCompleted suicide 12.8%median 1.7%0.4%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the benzodiazepine class

DrugName typeReportsLatest 12 monthsMarked serious
Alprazolamgeneric48,2632,27190.4%
Diazepamgeneric40,0602,76294.8%
Lorazepamgeneric33,3072,01090%
Xanaxbrand17,44452078.2%
Midazolamgeneric11,29987292.6%
Oxazepamgeneric10,7091,20099.1%
Valiumbrand9,65047784%
Clobazamgeneric8,00571289.1%
Temazepamgeneric7,42230890.7%
Klonopinbrand5,8325656.5%
Ativanbrand5,31825577.8%
Onfibrand3,5434157.5%
Midazolam hydrochloridegeneric1,73112588.6%
Triazolamgeneric1,4796684.3%
Restorilbrand1,0186679.8%

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Questions about Clonazepam reports

How many adverse event reports has FDA received for Clonazepam?

37,432 reports list Clonazepam as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 2,530 of them arrived in the latest 12 months. Another 82,253 list it only as a concomitant medication.

What reactions are recorded in Clonazepam reports?

completed suicide (12.8%), toxicity to various agents (11.9%), drug ineffective (11.5%), drug abuse (7.1%) and drug interaction (7%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Clonazepam was responsible.

How serious are the reports?

86.7% are marked serious by the reporter. Among the outcomes recorded, 29.9% of reports include death and 31.9% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

other health professional (35.1%), physician (29.5%) and consumer or non-health professional (23.4%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Clonazepam rising?

2,530 reports in the 12 months to June 2026, close to the 2,613 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Clonazepam was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Clonazepam?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Clonazepam as a suspect or interacting product; reports listing it only as a concomitant medication (82,253) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.