Lioresal (baclofen): adverse event reports filed with FDA

11,183

reports as suspect product

0.1% of all reports · about 497 a year

7

reports, 12 months to June 2026

7 in the 12 months before

71.5%

marked serious by the reporter

77.9% across the class

9.7%

record death among outcomes, as reported

1,080 reports · not verified by FDA

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

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Lioresal (baclofen) reports recording the termmedian drug in gamma-aminobutyric acid-ergic agonist

1. Muscle spasticity16.8%1,882
2. Hypertonia15%1,681
3. Drug ineffectivethe medicine did not work as expected14.5%1,620
4. Drug withdrawal syndromesymptoms on stopping a medicine12.1%1,348
5. Painpain, site not specified8.4%935
6. Overdosea dose above the recommended amount7.2%800
7. Muscle spasmsmuscle cramps6.1%677
8. Therapeutic response decreasedthe medicine worked less well5%564
9. Pruritusitching4.9%549
10. Somnolencedrowsiness4.7%528
11. Hypotonia4.6%513
12. Pyrexiafever4.3%480
13. Withdrawal syndrome3.9%439
14. Implant site infection3.9%434
15. Infectionan infection, type not specified3.9%431
16. Nauseafeeling sick3.4%383
17. Condition aggravatedthe condition being treated got worse3.3%365
18. Vomitingbeing sick3.2%361
19. Device failurethe device failed3.1%347
20. No therapeutic response3.1%347
21. Headachehead pain3%340
22. Deaththe patient died; cause not stated by this term2.9%324
23. Underdoseless than the intended dose2.7%306
24. Falla fall2.5%283
25. Hyperhidrosisexcessive sweating2.5%279
26. Complication associated with device2.5%274
27. Medical device complicationa complication with the device2.5%274
28. Device dislocationthe device moved out of position2.4%270
29. Urinary tract infectionbladder or urinary infection2.4%269
30. Convulsion2.3%259

Top 30 of 1,069 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 3 drugs in the gamma-aminobutyric acid-ergic agonist 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 35,901 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

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 89% of reports give the United States as the country of the event or reporter.

Reason for use recorded

The indication field is filled in by the reporter and is often blank; shares are of all 11,183 reports.

Drugs most often listed in the same reports

Other products listed in reports where Lioresal (baclofen) 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

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 gamma-aminobutyric acid-ergic agonist class

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.

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 Lioresal (baclofen) as a suspect or interacting product; reports listing it only as a concomitant medication (2,846) 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.