Briviact (brivaracetam) is a prescription medication used to treat focal onset seizures, sometimes called partial-onset seizures. These are seizures that start in one specific area of the brain rather than across the entire brain at once. Briviact is approved for adults and children aged 16 and older, and it can be used on its own or alongside other seizure medications.
How Briviact Works in the Brain
Briviact belongs to a class of seizure medications that target a specific protein on nerve cells called SV2A. This protein sits on tiny sacs inside neurons that store and release chemical messengers. By binding tightly to SV2A, Briviact reduces the release of glutamate, a brain chemical that excites nerve cells and plays a central role in triggering seizures. Less glutamate release means less abnormal electrical activity spreading through the brain.
If this mechanism sounds familiar, it’s because Briviact is chemically related to levetiracetam (Keppra), one of the most widely prescribed seizure medications in the world. Both drugs lock onto the same protein, but Briviact binds with at least 100 times greater selectivity for SV2A compared to similar proteins (SV2B and SV2C). This tighter, more selective binding is a key reason Briviact was developed as a next-generation option.
How It Compares to Keppra
One of the biggest practical differences between Briviact and Keppra is behavioral side effects. Keppra is effective but well known for causing irritability, hostility, and mood changes in some patients. In clinical trials, 3% to 4% of people taking Keppra experienced hostility, and larger real-world studies have found Keppra causes significantly more behavioral and psychiatric side effects than many other seizure medications.
Briviact appears to be easier on mood for most people. In a systematic review published in Epilepsy & Behavior, switching from Keppra to Briviact led to improvement in behavioral side effects in roughly two-thirds of patients (weighted mean of 66.6%). This makes Briviact a common alternative for people who respond well to Keppra’s seizure control but struggle with its impact on mood or personality.
Available Forms and Typical Dosing
Briviact comes in three forms: oral tablets, an oral solution, and an injectable (IV) version for hospital settings. Tablets are available in 10 mg, 25 mg, 50 mg, 75 mg, and 100 mg strengths. The oral solution delivers 10 mg per milliliter, which is useful for people who have difficulty swallowing pills or need precise dose adjustments.
The standard starting dose for adults is 50 mg taken twice a day, for a total of 100 mg per day. Unlike many seizure medications, Briviact does not require a slow buildup period. You can start at the full therapeutic dose right away. Depending on how well it works and how you tolerate it, the dose can be lowered to 25 mg twice daily or raised to a maximum of 100 mg twice daily (200 mg per day).
Common Side Effects
In pooled clinical trials involving over 800 patients, the most frequently reported side effects were:
- Drowsiness and sedation: 16% of patients (vs. 8% on placebo)
- Dizziness: 12% (vs. 7% on placebo)
- Fatigue: 9% (vs. 4% on placebo)
- Nausea or vomiting: 5% (vs. 3% on placebo)
- Coordination and balance problems: 3% (vs. 1% on placebo)
- Irritability: 3% (vs. 1% on placebo)
- Constipation: 2% (vs. 0% on placebo)
Drowsiness is by far the most common issue, and it tends to be most noticeable in the first few weeks. Many people find it lessens as their body adjusts. Because dizziness and sedation are relatively frequent, it’s worth being cautious with driving or operating machinery until you know how the medication affects you.
Psychiatric and Mood-Related Warnings
Like all seizure medications, Briviact carries a warning about suicidal thoughts and behavior. This is a class-wide FDA warning that applies broadly to anti-seizure drugs, not something unique to Briviact. Still, it means you and the people close to you should watch for new or worsening depression, unusual mood shifts, or thoughts of self-harm, especially in the early weeks of treatment or after a dose change.
Briviact can also trigger psychiatric reactions in some people, including psychotic symptoms, depression, aggressive behavior, and anxiety. While these are less common than the everyday side effects listed above, they’re worth knowing about. If you notice personality changes or emotional symptoms that feel out of character, that information is important to share with your prescriber promptly.
How the Body Processes Briviact
Briviact has a plasma half-life of about 9 hours, which is why it’s taken twice a day to maintain steady levels. The body breaks it down primarily in the liver, and more than 95% of each dose is eliminated through the kidneys within 72 hours. Less than 10% leaves the body in its original form; the rest is excreted as inactive byproducts. Because liver enzymes play a role in processing the drug, people with significant liver impairment may need dose adjustments.
Who Briviact Is Designed For
Briviact fills a specific niche in epilepsy treatment. It’s designed for people with focal onset seizures, the most common seizure type in adults. These seizures can look very different from person to person. Some cause twitching in one hand or side of the face. Others produce unusual sensations, confusion, or brief periods of altered awareness. Some focal seizures spread and become full-body convulsions. Briviact is approved for all of these variations as long as the seizure originates in a focal area of the brain.
In practice, Briviact is often prescribed when someone needs an effective seizure medication with a lower risk of mood-related side effects, when Keppra worked well for seizure control but caused behavioral problems, or when a fast-starting medication is preferred since no titration period is required. The availability of tablet, liquid, and IV forms also makes it versatile for different clinical situations, from routine daily use to hospital care when a patient temporarily cannot take oral medication.