Short answer: Cenobamate (Xcopri) is a prescription antiseizure medicine for partial-onset seizures in adults, approved in 2019. It is a Schedule V controlled substance. In trials it made many people seizure-free, but it must be started slowly to reduce the risk of a serious allergic reaction called DRESS.
Key takeaways
- What it is: Cenobamate is an antiseizure medicine and a Schedule V controlled substance in the US.
- Main uses: Partial-onset seizures (adults).
- Timing: effects start in peak levels in 1 to 4 hours and last once-daily dosing.
- Most dangerous mix: Hormonal contraceptives, which can cause reduced effectiveness.
- Naloxone: it does not reverse this drug, but give it whenever opioids could be involved.
- Dependence risk: Low.
- Legal route: only with a prescription from a DEA-registered clinician, filled by a licensed pharmacy.
What is cenobamate?
Cenobamate treats focal (partial-onset) seizures in adults. In clinical trials, a notable share of people with hard-to-treat epilepsy became seizure-free at higher doses.
It works in two ways: it reduces persistent sodium currents and enhances GABA-A receptors.
Quick facts
| Fact | Cenobamate |
|---|---|
| Generic name | Cenobamate |
| Brand names | Xcopri |
| Drug class | Antiseizure medicine; sodium current and GABA-A modulator |
| US legal status | Schedule V, prescription only |
| Approved uses | Partial-onset seizures in adults |
| Forms | Tablets (12.5 to 200 mg), titration packs |
| Half-life | About 50 to 60 hours |
How long does cenobamate last?
- Starts working: Peak levels in 1 to 4 hours
- Effects last: Once-daily dosing
- Half-life: About 50 to 60 hours
Its half-life is 50 to 60 hours, so it takes over a week to clear.
Timing varies with the dose, the form, how it is taken, liver and kidney function, age, and other drugs taken at the same time.
What are the biggest risks of cenobamate?
Common side effects include sleepiness, dizziness, tiredness, double vision, and headache.
DRESS: a serious multi-organ allergic reaction occurred in early studies when doses were increased quickly; slow titration lowers the risk.
QT shortening: it shortens the QT interval and must not be used in people with familial short QT syndrome.
What should you never mix with cenobamate?
| Combined with | What happens | Label guidance |
|---|---|---|
| Hormonal contraceptives | Reduced effectiveness | Use additional or non-hormonal methods |
| Phenytoin, phenobarbital, clobazam | Higher levels of these drugs | Lower their doses |
| Lamotrigine, carbamazepine | Lower levels of these drugs | Dose adjustments may be needed |
| Alcohol and sedatives | More drowsiness | Use caution |
Check any combination with the DoseUses combination checker or ask a pharmacist.
What are the signs of a cenobamate overdose, and what should you do?
Overdose is expected to cause drowsiness, dizziness, unsteadiness, and possibly heart rhythm changes.
If someone may have overdosed
- Call 911 if the person is unresponsive, hard to wake, or breathing slowly.
- For advice when the person is awake and stable, call Poison Help at 1-800-222-1222 (US, free, 24 hours).
- If opioids could be involved, including pills not from a pharmacy, give naloxone if you have it. Naloxone does not reverse cenobamate, but it will not harm the person.
- Stay with the person and place them on their side if they are drowsy or vomiting.
What happens if you stop cenobamate suddenly?
Cenobamate has low misuse potential, which is why it is in Schedule V. The main danger of stopping suddenly is not withdrawal but a rise in seizures.
- DaysSeizure riskSeizures can return or become more frequent, including prolonged seizures.
- TaperGradual reductionThe label advises tapering over at least a week or longer.
- OngoingReassessChanges in seizure medicines should be planned with a neurologist.
See the withdrawal timelines and the full cenobamate withdrawal guide.
Is cenobamate legal?
In the United States, cenobamate is a Schedule V controlled substance. The only legal way to get it is with a prescription from a clinician registered with the Drug Enforcement Administration (DEA), filled by a licensed pharmacy. Depending on state law, that can be a physician, nurse practitioner, or physician assistant.
- Refills: Schedule V prescriptions can be refilled as the prescriber authorizes, subject to state law.
- Telehealth: federal flexibilities let DEA-registered clinicians prescribe Schedule II to V medicines after a telemedicine visit, without a prior in-person exam, through December 31, 2026. A permanent DEA rule was under final review in late 2026. State rules can be stricter.
- Monitoring: prescribers and pharmacists in most states check a prescription drug monitoring program, a database of controlled-substance prescriptions, before prescribing or dispensing.
Outside the United States
| Country | Status |
|---|---|
| United Kingdom | Prescription-only medicine; not controlled |
| European Union | Prescription only |
| International | Not under UN control |
Frequently asked questions about cenobamate
Why does Xcopri have to be started slowly?
Fast increases were linked to DRESS, a serious allergic reaction, so doses are raised every 2 weeks.
Is cenobamate effective?
In trials it substantially reduced seizures, and some people with hard-to-treat epilepsy became seizure-free.
Does cenobamate affect birth control?
Yes. It can make hormonal contraceptives less effective.
Why is Xcopri a controlled substance?
It produced euphoria-like effects at high doses in studies, so it is in Schedule V.
How long does cenobamate stay in your system?
Its half-life is 50 to 60 hours, so it takes over a week to clear.
Sources
- Xcopri (cenobamate) prescription information, DailyMed, US National Library of Medicine.
- Controlled Substance Schedules, DEA Diversion Control Division.
- Prescribing controlled substances via telehealth, US Department of Health and Human Services.
- BeSafeRx: Your Source for Online Pharmacy Information, US Food and Drug Administration.
- Safe Pharmacy, National Association of Boards of Pharmacy.
- One Pill Can Kill, US Drug Enforcement Administration.
- International drug control conventions, United Nations Office on Drugs and Crime.
This guide summarizes the sourced DoseUses Cenobamate profile, written from FDA labels, DEA rules, and federal health agencies. It is educational and is not medical advice. Last updated October 5, 2026.
