What the label lists and what reports show
Brivaracetam side effects
Brivaracetam's FDA label: “Most common adverse reactions (at least 5% for BRIVIACT and at least 2% more frequently than placebo) are somnolence/sedation, dizziness, fatigue, and nausea/vomiting.” FAERS holds 8,940 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fatigue (576 reports).
- Generic listed
- DEA Schedule V
Check it at the source: the brivaracetam FDA label on DailyMed (effective August 20, 2026, UCB, Inc.); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of BRIVIACT?BRIVIACT may cause serious side effects, including: See " What is the most important information I should know about BRIVIACT? " Nervous system problems. Drowsiness, tiredness, and dizziness are common with BRIVIACT, but can be severe. See " What should I avoid while taking BRIVIACT? " BRIVIACT can also cause problems with balance and coordination. Mental (psychiatric) symptoms. BRIVIACT can cause mood and behavior changes such as aggression, agitation, anger, anxiety, apathy, mood swings, depression, hostility, and irritability. Irritability and anxiety are common with BRIVIACT, and can be severe. People who take BRIVIACT can also get psychotic symptoms such as hallucinations (seeing or hearing things that are really not there), delusions (false or strange thoughts or beliefs), and unusual behavior. Serious allergic reactions. […]
Source: FDA drug label, NDA205836 (Ucb Inc), as published by UCB, Inc., effective August 20, 2026 (SPL set 3cf2f439-0e97-443e-8e33-25ecef616f6c), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (at least 5% for BRIVIACT and at least 2% more frequently than placebo) are somnolence/sedation, dizziness, fatigue, and nausea/vomiting.
Table 4: Adverse Reactions in Pooled Placebo-Controlled Adjunctive Therapy Studies in Adult Patients with Partial-Onset Seizures (BRIVIACT 50 mg/day, 100 mg/day, and 200 mg/day)
| Adverse Reactions | BRIVIACT (N=803) % | Placebo (N=459) % |
|---|---|---|
| Nausea/vomiting symptoms | 5 | 3 |
| Constipation | 2 | 0 |
| Somnolence and sedation | 16 | 8 |
| Dizziness | 12 | 7 |
| Fatigue | 9 | 4 |
| Cerebellar coordination and balance disturbances Cerebellar coordination and balance… | 3 | 1 |
| Irritability | 3 | 1 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following serious adverse reactions are described elsewhere in labeling: Suicidal Behavior and Ideation [see Warnings and Precautions (5.1) ] Neurological Adverse Reactions [see Warnings and Precautions (5.2) ] Psychiatric Adverse Reactions [see Warnings and Precautions (5.3) ] Hypersensitivity: Bronchospasm and Angioedema [see Warnings and Precautions (5.4) ] Serious Dermatologic Reactions [see Warnings and Precautions (5.5) ] Withdrawal of Antiepileptic Drugs [see Warnings and Precautions (5.6) ] Adults: Most common adverse reactions (at least 5% for BRIVIACT and at least 2% more frequently than placebo) are somnolence/sedation, dizziness, fatigue, and nausea/vomiting. ( 6.1 ) Pediatric Patients: Most common adverse reactions are similar to those seen in adult patients. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact UCB, Inc. at 1-844-599-2273 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. In all controlled and uncontrolled trials performed in adult epilepsy patients, BRIVIACT was administered as adjunctive therapy to 2437 patients. …
Source: FDA drug label, NDA205836 (Ucb Inc), as published by UCB, Inc., effective August 20, 2026 (SPL set 3cf2f439-0e97-443e-8e33-25ecef616f6c), via openFDA; the full label on DailyMed
What do FAERS reports show?
8,940 reports list brivaracetam among the medicines taken, each a report of something that happened, not proof the medicine caused it; 446 are coded as a death and 2,446 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 17 reactions below, 9 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Brivaracetam: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions