Felbamate

Felbamate is a prescription medicine used for the treatment of seizures.

• Felbamate is available under the following different brand names: Felbatol

Common side effects of Felbamate include:

• drowsiness,
• dizziness,
• nausea,
• vomiting,
• diarrhea,
• constipation,
• trouble sleeping (insomnia),
• headache,
• hiccups,
• changes in weight or appetite,
• nervousness,
• tired feeling,
• headache,
• acne,
• itching or skin rash,
• runny or stuffy nose,
• blurred vision, or
• changes in the sense of taste.

Serious side effects of Felbamate include:

• ear pain, or
• vision changes (e.g., double vision).

Rare side effects of Felbamate include:

• none

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors;
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out. 

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult and pediatric dosage

Tablets

• 400 mg
• 600 mg

Oral suspension

• 600 mg/5 mL

Seizures

Adult dosage

• Monotherapy
  • 1200 mg/day orally divided every 6-8 hours initially; titrate previously untreated patients with caution, increasing the dose in 600 mg increments every 2 weeks to 2400 mg/day based on clinical response and thereafter to 3600 mg/day if necessary
  • Conversion to monotherapy
    • Initial: 1200 mg/day orally divided every 6-8 hours; reduce the dose of concomitant anticonvulsant(s) by 33% at the initiation of felbamate therapy
    • Week 2: Increase felbamate dose to 2400 mg/day while reducing the dosage of other anticonvulsant(s) up to an additional 33% of the original dosage
    • Week 3: Increase felbamate dose up to 3600 mg/day and continue to reduce the dosage of other anticonvulsant(s) as clinically indicated
• Adjunctive therapy
  • Initial: 1200 mg/day orally divided every 6-8 hours; increase by 1200 mg/day once per week up to 3600 mg/day orally divided every 6-8 hours
  • Decrease the concomitant dose of carbamazepine, phenytoin, phenobarbital, or valproic acid by 20 % when initiating felbamate dosing; as felbamate dose is increased, further dosage reductions of concomitant anticonvulsant therapies may be necessary

Pediatric dosage

• Aged below 14 years: Safety and efficacy not established
• Aged above 14 years:
• Monotherapy
• 1200 mg/day orally divided every 6-8 hours initially; titrate previously untreated patients with caution, increasing the dose in 600 mg increments every 2 weeks to 2400 mg/day based on clinical response and thereafter to 3600 mg/day if necessary
• Conversion to monotherapy
  • Initial: 1200 mg/day orally divided every 6-8 hours; reduce the dose of concomitant anticonvulsant(s) by 33% at the initiation of felbamate therapy
  • Week 2: Increase felbamate dose to 2400 mg/day while reducing the dosage of other anticonvulsant(s) up to an additional 33% of the original dosage
  • Week 3: Increase felbamate dose up to 3600 mg/day and continue to reduce the dosage of other anticonvulsant(s) as clinically indicated
• Adjunctive therapy
  • Initial: 1200 mg/day orally divided every 6-8 hours; increase by 1200 mg/day once per week up to 3600 mg/day orally divided every 6-8 hours
  • Decrease the concomitant dose of carbamazepine, phenytoin, phenobarbital, or valproic acid by 20 % when initiating felbamate dosing; as felbamate dose is increased, further dosage reductions of concomitant anticonvulsant therapies may be necessary

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Felbamate has severe interactions with no other drugs.
• Felbamate has serious interactions with at least 28 other drugs.
• Felbamate has moderate interactions with at least 70 other drugs.
• Felbamate has minor interactions with at least 38 other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, or if you have health questions or concerns.

Contraindications

• Hypersensitivity to carbamates; history of blood dyscrasia, hepatic impairment

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Felbamate?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Felbamate?”

Cautions

• Increased risk of suicidal behavior reported with anticonvulsant use; monitor patients for changes in behavior that might indicate suicidal behavior
• Associated with increased incidence of aplastic anemia and acute hepatic failure, use only when alternative therapy is unsuitable and benefits outweigh risks
• Use caution in renal impairment
• Not for use as first-line therapy in epilepsy; for use when benefits outweigh risks
• Do not discontinue therapy abruptly

Pregnancy and Lactation

• Use with caution if benefits outweigh risks during pregnancy
  • Lactation
  • Excreted in milk; not recommended