Reported Reactions

Drugs › Benzodiazepine

Brand name · Clobazam

Onfi: adverse event reports filed with FDA

3,543 reports list it as a suspect or interacting product, 2011–2026. Class: Benzodiazepine.

3,543
reports as suspect product
0% of all reports · about 240 a year
41
reports, 12 months to June 2026
42 in the 12 months before
57.5%
marked serious by the reporter
88.1% across the class
3%
record death among outcomes, as reported
106 reports · not verified by FDA

Between October 2011 and June 2026, 3,543 adverse event reports received by FDA list the brand name Onfi (clobazam) as a suspect or interacting product. Reports that mention it only as a concomitant medication (3,819) are left out of every figure here.

In the 12 months to June 2026, 41 reports listed it, close to the 42 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 240 reports a year and 0% of the 20,646,523 reports in the database, and 1.5% 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 MedDRA terms listed most often are seizure (23.8%), somnolence (10%) and drug ineffective (6.6%). A report can list several reactions, so shares add to more than 100%; 413 different terms appear across these reports. Seizure is recorded in 23.8% of these reports, a larger share than in the median benzodiazepine drug (1.9%).

57.5% of the reports are marked serious by the reporter (88.1% across the class); 3% record death among the outcomes and 18.7% record hospitalisation, as reported. 50.9% of the reports came from consumers, and the largest patient age group is 18 to 44 (14.9%). 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

03059Jul 2021: 59Aug 2021: 7Sep 2021: 6Oct 2021: 7Nov 2021: 2Dec 2021: 42022Jan 2022: 16Feb 2022: 4Mar 2022: 12Apr 2022: 5May 2022: 4Jun 2022: 2Jul 2022: 6Aug 2022: 4Sep 2022: 3Oct 2022: 6Nov 2022: 0Dec 2022: 32023Jan 2023: 3Feb 2023: 0Mar 2023: 2Apr 2023: 0May 2023: 3Jun 2023: 6Jul 2023: 6Aug 2023: 8Sep 2023: 0Oct 2023: 6Nov 2023: 7Dec 2023: 12024Jan 2024: 9Feb 2024: 6Mar 2024: 3Apr 2024: 6May 2024: 1Jun 2024: 0Jul 2024: 0Aug 2024: 3Sep 2024: 4Oct 2024: 4Nov 2024: 1Dec 2024: 32025Jan 2025: 9Feb 2025: 4Mar 2025: 4Apr 2025: 4May 2025: 4Jun 2025: 2Jul 2025: 2Aug 2025: 1Sep 2025: 3Oct 2025: 5Nov 2025: 5Dec 2025: 32026Jan 2026: 7Feb 2026: 3Mar 2026: 2Apr 2026: 4May 2026: 2Jun 2026: 4

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

03166322011: 1320112012: 3562013: 36120132014: 3002015: 39320152016: 5342017: 63220172018: 2242019: 20820192020: 1592021: 14820212022: 652023: 4220232024: 402025: 4620252026: 22

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Onfi reports recording the termmedian drug in benzodiazepine

  1. Seizurea fit or convulsion23.8%845
  2. Somnolencedrowsiness10%355
  3. Drug ineffectivethe medicine did not work as expected6.6%235
  4. Drug withdrawal convulsions5.7%203
  5. Fatiguetiredness5.6%199
  6. Convulsion5.4%192
  7. Aggressionaggressive behaviour4.4%157
  8. Drug dose omissiona dose was missed3.5%125
  9. Insomniadifficulty sleeping3.5%123
  10. Abnormal behaviourunusual behaviour3.3%117
  11. Drug interactionan interaction between medicines3.1%111
  12. Off label useused for a purpose or in a way not on the label3%107
  13. Falla fall3%106
  14. Sedationdrowsiness from a medicine3%105
  15. Dizzinesslight-headedness or unsteadiness2.9%104
  16. Irritabilityirritability2.4%84
  17. Weight increasedweight gain2.4%84
  18. Rashskin rash2.2%79
  19. Headachehead pain2.1%75
  20. Gait disturbancedifficulty walking2.1%74
  21. Feeling abnormalfeeling odd or not right2%71
  22. Product dose omissiona dose was missed2%71
  23. Hypersomniasleeping too much2%70
  24. Balance disorderproblems with balance1.8%65
  25. Vomitingbeing sick1.8%65
  26. Constipationconstipation1.8%63
  27. Pneumonialung infection1.7%60
  28. Lethargysluggishness1.7%59
  29. Memory impairmentmemory problems1.6%58

Top 30 of 413 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

Death3%106
Life-threatening1.4%51
Hospitalisation (initial or prolonged)18.7%661
Disability0.8%28
Congenital anomaly0.5%19
Other serious40%1,417
Not serious42.5%1,505

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 21.5%53
2 to 1110.4%367
12 to 174.3%153
18 to 4414.9%528
45 to 646.4%228
65 to 740.9%31
75 and over0.5%17
Age not given61.1%2,166

Patient sex

Female43.3%1,535
Male39.2%1,388
Not given17.5%620

Who reported

Physician27.8%986
Pharmacist2.2%78
Other health professional17.6%623
Lawyer0%1
Consumer or non-health professional50.9%1,803
Not given1.5%52

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 95.7% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Epilepsy76121.5%
Lennox-gastaut syndrome3359.5%
Seizure3058.6%
Partial seizures1263.6%
Convulsion972.7%
Generalised tonic-clonic seizure551.6%

The indication field is filled in by the reporter and is often blank; shares are of all 3,543 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Onfi reports
Keppra67219%
Vimpat38911%
Lamictal38210.8%
Depakote36710.4%
Topamax2597.3%
Epidiolex2005.6%
Trileptal1775%
Zonegran1554.4%
Clonazepam1434%
Phenobarbital1203.4%

Other products listed in reports where Onfi 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

MeasureOnfiBenzodiazepineAll reports
Reports as suspect product3,543244,28920,646,523
Share of that pool—1.5%0%
Reports, latest 12 months41—1,332,454
Marked serious57.5%88.1%57.4%
Death recorded among outcomes, per 1,000 reports3029791
Hospitalisation recorded, per 1,000 reports187346213
Consumer-filed share50.9%21.3%45.8%
Top term, share of reportsSeizure 23.8%median 1.9%0.5%

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%
Clonazepamgeneric37,4322,53086.7%
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%
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 Onfi reports

How many adverse event reports has FDA received for Onfi?

3,543 reports list Onfi as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 41 of them arrived in the latest 12 months. Another 3,819 list it only as a concomitant medication.

What reactions are recorded in Onfi reports?

seizure (23.8%), somnolence (10%), drug ineffective (6.6%), drug withdrawal convulsions (5.7%) and fatigue (5.6%). 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 Onfi was responsible.

How serious are the reports?

57.5% are marked serious by the reporter. Among the outcomes recorded, 3% of reports include death and 18.7% 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?

consumer or non-health professional (50.9%), physician (27.8%) and other health professional (17.6%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Onfi rising?

41 reports in the 12 months to June 2026, close to the 42 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 Onfi 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 Onfi?

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 Onfi as a suspect or interacting product; reports listing it only as a concomitant medication (3,819) 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.