cenobamate vs phenobarbital

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Side-by-side comparison of cenobamate and phenobarbital. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

moderate Known Drug Interaction

( 7.1 ) Phenobarbital and Clobazam: Reduce dosage as needed when used concomitantly with XCOPRI. phenobarbital ↑ plasma concentrations Because of a potential for an increase in the risk of adverse reactions from these drugs, consider a reduction in dosage of phenobarbital or clobazam, as clinically appropriate, when used concomitantly with XCOPRI.

Drug Class
cenobamate Anticonvulsant
phenobarbital Anticonvulsant (Barbiturate)
Type
cenobamate Prescription
phenobarbital Prescription
Summary
cenobamate

Xcopri is a medicine used to treat partial-onset seizures in adults. It works by reducing the irregular electrical activity in the brain that causes seizures.

phenobarbital

Phenobarbital is a medicine that can help control seizures and calm you down. It belongs to a class of drugs called barbiturates.

What It Treats
cenobamate

Xcopri is used to treat partial-onset seizures in adults. Partial-onset seizures start in one area of the brain. This medicine can help reduce how often you have seizures.

phenobarbital

This medicine is used to treat generalized and partial seizures. Seizures are caused by unusual electrical activity in the brain. Phenobarbital helps to reduce this activity and prevent seizures.

How It Works
cenobamate

Xcopri helps to control seizures by affecting brain activity. It reduces the excitability of brain cells. This helps to prevent the spread of seizure activity.

phenobarbital

Phenobarbital works by slowing down the activity of your brain and nervous system. It increases the effects of a natural chemical in the body called GABA. This helps to reduce seizures and promote relaxation.

Common Side Effects
cenobamate
  • Feeling sleepy
  • Dizziness
  • Feeling tired
  • Double vision
  • Headache
phenobarbital
  • Drowsiness
  • Sedation
  • Lethargy
  • Vertigo
FAERS Reports
cenobamate
  • Seizure 1,815
  • Fatigue 672
  • Somnolence 660
  • Dizziness 537
  • Fall 368
phenobarbital
  • Seizure 1,534
  • Drug Interaction 635
  • Toxicity To Various Agents 621
  • Status Epilepticus 482
  • Multiple-Drug Resistance 442
Serious Warnings
cenobamate

This medicine can cause a serious allergic reaction called DRESS, which can affect multiple organs. It can also cause liver problems. Tell your doctor right away if you have a fever, rash, swollen lymph nodes, or yellowing of your skin or eyes. Xcopri may cause you to have suicidal thoughts or behaviors. Watch for changes in your mood.

phenobarbital

You should not take this medicine if you are allergic to barbiturates. Also, do not take it if you have a history of porphyria, severe liver problems, or breathing problems.

Pregnancy
cenobamate

Tell your doctor if you are pregnant or plan to become pregnant. Xcopri may harm your unborn baby. There is a pregnancy registry for women who take anti-seizure medicines like Xcopri.

phenobarbital

Tell your doctor if you are pregnant or plan to become pregnant. Phenobarbital can harm an unborn baby. Talk to your doctor about the risks and benefits of taking this medicine while breastfeeding.

Also Compare, Nearby Drugs

How to Read This cenobamate vs phenobarbital Comparison

cenobamate is classified in the Anticonvulsant drug class, while phenobarbital sits within the Anticonvulsant (Barbiturate) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, cenobamate has 4,052 submissions while phenobarbital has 3,714. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to cenobamate causes the levels of phenobarbital in your blood to go up. this makes it more likely that you will have a bad reaction to the phenobarbital.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for cenobamate or phenobarbital.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.