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oxcarbazepine vs phenobarbital

Side-by-side comparison of oxcarbazepine and phenobarbital. 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

Reduced dose of phenytoin may be required ( 7.1 ) • Carbamazepine, Phenytoin, and Phenobarbital: Decreased plasma levels of MHD (the active metabolite). 7.2 Effect of Other Drugs on Oxcarbazepine Strong inducers of cytochrome P450 enzymes and/or inducers of UGT (e.g., rifampin, carbamazepine, phenytoin and phenobarbital) have been shown to decrease the plasma/serum levels of MHD, the active metabolite of oxcarbazepine (25% to 49%) [see Clinical Pharmacology ( 12.3 )].

Recommendation: Your doctor may need to adjust your dose of oxcarbazepine to ensure it stays at a level that helps you.

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

Oxcarbazepine is a medicine used to treat seizures. It helps to control seizures in adults and children.

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
oxcarbazepine

Oxcarbazepine is used to treat partial-onset seizures. These seizures start in one part of the brain. It can be used alone or with other seizure medicines.

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
oxcarbazepine

Oxcarbazepine works by reducing the electrical activity in the brain. This helps to prevent seizures. It stabilizes overexcited nerve cells.

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
oxcarbazepine
  • Dizziness
  • Sleepiness
  • Double vision
  • Feeling tired
  • Nausea
phenobarbital
  • Drowsiness
  • Sedation
  • Lethargy
  • Vertigo
FAERS Reports
oxcarbazepine
  • Seizure 2,805
  • Tiredness 1,607
  • Feeling dizzy 1,519
  • Convulsion 1,465
  • Headache 1,434
phenobarbital
  • Seizure 1,534
  • Medicine interacting with another medicine 635
  • Poisoning from different things 621
  • Prolonged seizure 482
  • Not responding to multiple medicines 442
Serious Warnings
oxcarbazepine

This medicine can cause low sodium levels in your blood. Your doctor should check your sodium levels, especially if you take other medicines that can also lower sodium. This medicine may cause suicidal thoughts or actions. Contact your doctor right away if you have any sudden changes in mood, thoughts, or feelings.

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
oxcarbazepine

Oxcarbazepine may harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. There is a pregnancy registry for women who take this medicine during pregnancy. You can enroll by calling 1-888-233-2334.

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 oxcarbazepine vs phenobarbital Comparison

oxcarbazepine 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, oxcarbazepine has 8,830 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 minor interaction flagged in FDA labeling, attributed to phenobarbital causes your body to process and remove the active part of oxcarbazepine more quickly than usual.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between oxcarbazepine and phenobarbital - always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.