cenobamate vs phenytoin

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

minor Known Drug Interaction

7 DRUG INTERACTIONS Phenytoin: Gradually decrease phenytoin dosage by up to 50%. carbamazepine ↓ plasma concentrations phenytoin ↑ plasma concentrations Because of a potential 2-fold increase in phenytoin levels, gradually decrease phenytoin dosage by up to 50% as XCOPRI is being titrated.

Drug Class
cenobamate Anticonvulsant
phenytoin Anticonvulsant (Hydantoin)
Type
cenobamate Prescription
phenytoin 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.

phenytoin

Phenytoin injection is used to treat certain types of seizures. It can also prevent seizures during or after neurosurgery.

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.

phenytoin

This medicine treats generalized tonic-clonic status epilepticus, a type of prolonged seizure. It also helps prevent and treat seizures that may happen during or after brain surgery. Sometimes, it can be used for a short time instead of the oral form of phenytoin when you cannot take the medicine by mouth.

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.

phenytoin

Phenytoin works by slowing down the signals in the brain that cause seizures. It stabilizes nerve cell membranes, reducing excessive electrical activity. This helps to prevent seizures from starting or spreading.

Common Side Effects
cenobamate
  • Feeling sleepy
  • Dizziness
  • Feeling tired
  • Double vision
  • Headache
phenytoin

No common side effects listed.

FAERS Reports
cenobamate
  • Seizure 1,815
  • Fatigue 672
  • Somnolence 660
  • Dizziness 537
  • Fall 368
phenytoin
  • Drug Interaction 1,547
  • Seizure 1,382
  • Toxicity To Various Agents 1,353
  • Convulsion 1,262
  • Status Epilepticus 791
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.

phenytoin

This medicine can cause serious heart problems if given too quickly. The injection rate should not be faster than 50 mg per minute for adults, and 1 to 3 mg/kg/min (or 50 mg per minute, whichever is slower) for children. Your heart will be monitored closely during and after the injection.

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.

phenytoin

Taking phenytoin during pregnancy may increase the risk of birth defects. If you are pregnant or plan to become pregnant, talk to your doctor about the risks and benefits of this medicine.

Also Compare, Nearby Drugs

How to Read This cenobamate vs phenytoin Comparison

cenobamate is classified in the Anticonvulsant drug class, while phenytoin sits within the Anticonvulsant (Hydantoin) 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 phenytoin has 6,335. 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 minor interaction flagged in FDA labeling, attributed to cenobamate slows down the body's ability to clear phenytoin, which can cause the drug to build up to dangerous levels. this can lead to a two-fold increase in the amount of phenytoin in your blood.. 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 phenytoin.

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