Briviact Side Effects: What to Expect and When to Call Your Doctor

What to Know Before You Start — and After

Every medication has side effects, and Briviact (brivaracetam) is no exception. The good news is that Briviact is generally well-tolerated compared to many other seizure medications. But knowing what to expect — and what's serious enough to call your doctor about — helps you manage your treatment with confidence.

This guide covers the common side effects, the serious ones, and practical tips for handling them.

What Is Briviact? (Quick Overview)

Briviact is the brand name for brivaracetam, an anticonvulsant medication made by UCB. It's approved by the FDA to treat partial-onset (focal) seizures in patients 1 month and older. It works by binding to a brain protein called SV2A, which helps regulate nerve cell signaling. Briviact is related to Levetiracetam (Keppra) but generally has fewer behavioral side effects.

For a deeper dive, see: What Is Briviact? Uses, Dosage, and What You Need to Know.

Common Side Effects

These side effects are reported most frequently in clinical trials. They're usually mild to moderate and often improve as your body adjusts to the medication (typically within the first few weeks):

• Drowsiness/sleepiness (somnolence) — The most common side effect. Reported in about 10-15% of patients. Usually worst when starting or increasing the dose.
• Dizziness — Reported in about 10% of patients. May be worse when standing up quickly.
• Fatigue — Feeling more tired than usual, especially in the first few weeks.
• Nausea — Some patients experience mild stomach upset, particularly when starting the medication.
• Vomiting — Less common than nausea but can occur.
• Balance problems — Some patients feel less steady on their feet.

What to do: These side effects are usually manageable. If drowsiness is a problem, talk to your doctor about taking more of your dose at bedtime. Avoid driving or operating heavy machinery until you know how Briviact affects you. Most of these improve within 2-4 weeks.

Serious Side Effects

These are less common but require medical attention:

Mood and Behavioral Changes

All anti-seizure medications carry an FDA warning about increased risk of suicidal thoughts and behavior. With Briviact specifically, some patients have reported:

• Irritability or agitation
• Anxiety or depression
• Aggression or anger
• Psychotic symptoms (rare)
• Suicidal thoughts

Important: While Briviact is often prescribed specifically because it causes fewer behavioral side effects than Levetiracetam (Keppra), these effects can still occur. Tell your doctor immediately if you notice significant mood changes, new depression, or any thoughts of self-harm.

Allergic Reactions

Rare but serious hypersensitivity reactions have been reported, including:

• Bronchospasm (tightening of airways)
• Angioedema (swelling of face, lips, tongue, or throat)

If you experience difficulty breathing or significant swelling, call 911 or go to the emergency room immediately.

Withdrawal Seizures

If you stop taking Briviact suddenly, you may experience withdrawal seizures, which can be more severe than your usual seizures. Never stop Briviact abruptly — your doctor will taper your dose gradually if you need to discontinue.

Side Effects in Specific Populations

Liver Problems

Briviact is processed by the liver. Patients with liver impairment may experience stronger effects and need lower doses (maximum 75 mg twice daily for any stage of hepatic impairment). Your doctor should monitor your liver function if you have known liver disease.

Pregnancy

There is limited data on Briviact use during pregnancy. Seizure medications in general carry risks during pregnancy, but uncontrolled seizures also pose serious risks. If you're pregnant or planning to become pregnant, discuss the risks and benefits with your neurologist. Don't stop your seizure medication without medical guidance.

Older Adults

Elderly patients may be more sensitive to the drowsiness and dizziness effects of Briviact. Starting at lower doses and increasing slowly is often recommended.

Children

Briviact is approved for children as young as 1 month old, with weight-based dosing. Side effects in children are similar to adults, with drowsiness and decreased appetite being most commonly reported.

How to Manage Side Effects

• Give it time. Many side effects improve within 2-4 weeks. If you're tolerating the medication reasonably well, your body may adjust.
• Adjust your schedule. If drowsiness is a problem, ask your doctor about taking a larger portion of your daily dose at bedtime.
• Stay hydrated. Drinking enough water can help with nausea and dizziness.
• Avoid alcohol. Briviact plus alcohol increases sedation significantly. Limit or avoid alcohol use.
• Keep a side effect diary. Track what you're experiencing and when. This helps your doctor make dosing decisions at follow-up appointments.
• Don't stop on your own. If side effects are intolerable, contact your doctor before making any changes. Stopping suddenly can cause withdrawal seizures.

When to Call Your Doctor

Contact your doctor if you experience:

• Mood changes, new depression, or thoughts of self-harm
• Side effects that don't improve after several weeks
• Side effects that interfere with daily life (excessive drowsiness, inability to work)
• Signs of allergic reaction (rash, swelling, difficulty breathing)
• Any new or worsening symptoms

Final Thoughts

Briviact is generally one of the better-tolerated seizure medications. Most side effects are mild and improve with time. The most important things to watch for are mood changes and allergic reactions — both are uncommon but need prompt attention.

If you're considering Briviact, learn more about how it works: How Does Briviact Work?. And if you're already taking it and having trouble finding it at your pharmacy, check: How to Check If a Pharmacy Has Briviact in Stock.