Generic name
Cyclobenzaprine hcl: adverse event reports filed with FDA
763 reports list it as a suspect or interacting product, 2004–2021. Class: Muscle relaxant.
- 763
- reports as suspect product
- 0% of all reports · about 34 a year
- 0
- reports, 12 months to June 2026
- 0 in the 12 months before
- 88.1%
- marked serious by the reporter
- 86.6% across the class
- 63%
- record death among outcomes, as reported
- 481 reports · not verified by FDA
Between January 2004 and September 2021, 763 adverse event reports received by FDA list cyclobenzaprine hcl, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (3,998) are left out of every figure here.
In the 12 months to June 2026, 0 reports listed it, and none in 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 34 reports a year and 0% of the 20,646,523 reports in the database, and 3.8% of the reports for the muscle relaxant 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 (36.8%), cardiac arrest (16%) and respiratory arrest (15.5%). A report can list several reactions, so shares add to more than 100%; 204 different terms appear across these reports. Completed suicide is recorded in 36.8% of these reports, a larger share than in the median muscle relaxant drug (18%).
88.1% of the reports are marked serious by the reporter (86.6% across the class); 63% record death among the outcomes and 18.1% record hospitalisation, as reported. 40.2% of the reports came from physicians, and the largest patient age group is 45 to 64 (34.6%). 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
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
Reactions recorded in the reports
share of Cyclobenzaprine hcl reports recording the termmedian drug in muscle relaxant
- Completed suicidedeath by suicide36.8%281
- Cardiac arrestthe heart stopped16%122
- Respiratory arrestbreathing stopped15.5%118
- Drug toxicity8.1%62
- Cardio-respiratory arrestthe heart and breathing stopped7.3%56
- Overdosea dose above the recommended amount6.3%48
- Multiple drug overdose5.5%42
- Toxicity to various agentspoisoning or toxic effect of one or more substances5.2%40
- Hypotensionlow blood pressure5.1%39
- Deaththe patient died; cause not stated by this term4.8%37
- Confusional stateconfusion4.3%33
- Intentional drug misuse3.9%30
- Drug abusemisuse of a medicine3.3%25
- Multiple drug overdose intentional3.3%25
- Falla fall3.1%24
- Coma3%23
- Poisoning3%23
- Somnolencedrowsiness3%23
- Drug interactionan interaction between medicines2.6%20
- Intentional misuse2.5%19
- Loss of consciousnesspassing out2.4%18
- Painpain, site not specified2.4%18
- Tachycardiafast heart rate2.4%18
- Intentional overdosea deliberate overdose2.2%17
- Vomitingbeing sick2.2%17
- Balance disorderproblems with balance2%15
- Drug hypersensitivityan allergic-type reaction to a medicine2%15
- Heart rate increaseda fast heart rate reading2%15
- Blood calcium decreased1.8%14
Top 30 of 204 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 8 drugs in the muscle relaxant 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
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 20,135 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
Patient sex
Who reported
Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 86.8% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Suicide attempt | 33 | 4.3% |
| Muscle spasms | 31 | 4.1% |
| Back pain | 7 | 0.9% |
| Completed suicide | 6 | 0.8% |
| Fibromyalgia | 6 | 0.8% |
| Ill-defined disorder | 4 | 0.5% |
The indication field is filled in by the reporter and is often blank; shares are of all 763 reports.
In context
| Measure | Cyclobenzaprine hcl | Muscle relaxant | All reports |
|---|---|---|---|
| Reports as suspect product | 763 | 20,135 | 20,646,523 |
| Share of that pool | — | 3.8% | 0% |
| Reports, latest 12 months | 0 | — | 1,332,454 |
| Marked serious | 88.1% | 86.6% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 630 | 512 | 91 |
| Hospitalisation recorded, per 1,000 reports | 181 | 265 | 213 |
| Consumer-filed share | 10.2% | 18.6% | 45.8% |
| Top term, share of reports | Completed suicide 36.8% | median 18% | 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 muscle relaxant class
| Drug | Name type | Reports | Latest 12 months | Marked serious |
|---|---|---|---|---|
| Cyclobenzaprine | generic | 8,750 | 560 | 90.5% |
| Carisoprodol | generic | 4,095 | 28 | 92.1% |
| Methocarbamol | generic | 2,111 | 245 | 79.6% |
| Cyclobenzaprine hydrochloride | generic | 1,591 | 115 | 86.3% |
| Soma | brand | 1,316 | 5 | 76.3% |
| Metaxalone | generic | 925 | 12 | 73.7% |
| Robaxin | brand | 584 | 29 | 57.5% |
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 Cyclobenzaprine hcl reports
How many adverse event reports has FDA received for Cyclobenzaprine hcl?
763 reports list Cyclobenzaprine hcl as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 0 of them arrived in the latest 12 months. Another 3,998 list it only as a concomitant medication.
What reactions are recorded in Cyclobenzaprine hcl reports?
completed suicide (36.8%), cardiac arrest (16%), respiratory arrest (15.5%), drug toxicity (8.1%) and cardio-respiratory arrest (7.3%). 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 Cyclobenzaprine hcl was responsible.
How serious are the reports?
88.1% are marked serious by the reporter. Among the outcomes recorded, 63% of reports include death and 18.1% 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?
physician (40.2%), other health professional (24.9%) and not given (14.2%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Cyclobenzaprine hcl rising?
0 reports in the 12 months to June 2026, and none in 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 Cyclobenzaprine hcl 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 Cyclobenzaprine hcl?
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 Cyclobenzaprine hcl as a suspect or interacting product; reports listing it only as a concomitant medication (3,998) 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.