Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Felbatol

Descriptions


Felbamate is used alone or together with other medicines to control partial seizures (convulsions) in the treatment of epilepsy, after other therapies have failed or are not right for the patient. It is also used in children to control partial and generalized seizures caused by Lennox-Gastaut syndrome.

Felbamate belongs to a class of medicines called anticonvulsants. It acts in the brain to prevent seizures. However, this medicine cannot cure epilepsy and will only work to control seizures for as long as you continue to take it.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Tablet
  • Suspension

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of felbamate to treat seizures other than Lennox-Gastaut syndrome in children. Safety and efficacy have not been established.

Geriatric

Although appropriate studies on the relationship of age to the effects of felbamate have not been performed in the geriatric population, no geriatric-specific problems have been documented to date. However, elderly patients are more likely to have age-related heart, kidney, or liver problems, which may require caution and an adjustment in the dose for patients receiving felbamate.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

  • Bepridil
  • Cisapride
  • Dronedarone
  • Levoketoconazole
  • Mesoridazine
  • Pimozide
  • Piperaquine
  • Saquinavir
  • Sparfloxacin
  • Terfenadine
  • Thioridazine
  • Ziprasidone

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Adagrasib
  • Amiodarone
  • Amisulpride
  • Anagrelide
  • Apomorphine
  • Aripiprazole
  • Aripiprazole Lauroxil
  • Arsenic Trioxide
  • Atazanavir
  • Buprenorphine
  • Buserelin
  • Calcifediol
  • Ceritinib
  • Chloroquine
  • Citalopram
  • Clarithromycin
  • Clofazimine
  • Clopidogrel
  • Clothiapine
  • Clozapine
  • Crizotinib
  • Dabrafenib
  • Dasatinib
  • Degarelix
  • Delamanid
  • Deslorelin
  • Deutetrabenazine
  • Dexmedetomidine
  • Domperidone
  • Donepezil
  • Drospirenone
  • Efavirenz
  • Encorafenib
  • Entrectinib
  • Escitalopram
  • Ethinyl Estradiol
  • Etrasimod
  • Fexinidazole
  • Fingolimod
  • Fluconazole
  • Fluoxetine
  • Formoterol
  • Foscarnet
  • Fostemsavir
  • Gepirone
  • Gestodene
  • Glasdegib
  • Gonadorelin
  • Goserelin
  • Histrelin
  • Hydroxychloroquine
  • Hydroxyzine
  • Inotuzumab Ozogamicin
  • Ivabradine
  • Ivosidenib
  • Ketoconazole
  • Lefamulin
  • Lenvatinib
  • Leuprolide
  • Levofloxacin
  • Lofexidine
  • Macimorelin
  • Methadone
  • Methotrexate
  • Metronidazole
  • Mirtazapine
  • Mobocertinib
  • Moxifloxacin
  • Nafarelin
  • Nilotinib
  • Norethindrone
  • Norgestimate
  • Olanzapine
  • Ondansetron
  • Orlistat
  • Osilodrostat
  • Osimertinib
  • Oxaliplatin
  • Ozanimod
  • Pacritinib
  • Panobinostat
  • Paroxetine
  • Pasireotide
  • Pazopanib
  • Pexidartinib
  • Phenobarbital
  • Pimavanserin
  • Pitolisant
  • Ponesimod
  • Posaconazole
  • Primidone
  • Quetiapine
  • Quizartinib
  • Relugolix
  • Ribociclib
  • Selpercatinib
  • Sertraline
  • Sevoflurane
  • Siponimod
  • Solifenacin
  • Sotalol
  • Sulpiride
  • Sunitinib
  • Tacrolimus
  • Trazodone
  • Triclabendazole
  • Triptorelin
  • Ulipristal
  • Valproic Acid
  • Vandetanib
  • Vardenafil
  • Vemurafenib
  • Venlafaxine
  • Vilanterol
  • Vinflunine
  • Voclosporin
  • Zuclopenthixol

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Carbamazepine
  • Clobazam
  • Fosphenytoin
  • Ginkgo
  • Methsuximide
  • Phenytoin
  • Warfarin

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Blood problems (e.g., aplastic anemia), history of or
  • Liver problems, history of—Should not be used in patients with these conditions.
  • Depression or
  • Mental illness—Use with caution. May make these conditions worse.
  • Kidney disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.

Proper Use

This medicine should not be the first medicine you use to treat your condition. It is meant to be used only after you have tried other medicines that have not worked or have caused unwanted side effects.

Take this medicine only as directed by your doctor, to benefit your condition as much as possible. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

It is very important that you understand the risks and benefits of felbamate before using it. You may also be asked to sign a patient/physician acknowledgment form and read the Medication Guide to make sure you understand the information about this medicine. Be sure to ask your doctor about anything you do not understand.

For patients taking the oral liquid form of this medicine:

  • Shake the bottle well before measuring the dose.
  • Use a specially marked measuring spoon, a plastic syringe, or a small marked measuring cup to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

To lessen stomach upset, felbamate may be taken with food, unless your doctor has told you to take it on an empty stomach.

This medicine can be used with other seizure medicines. Keep using all of your seizure medicines unless your doctor tells you to stop.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage forms (suspension or tablets):
    • For epilepsy:
      • Adults and teenagers 14 years of age and older—At first, usually 1200 milligrams (mg) per day, divided into three or four smaller doses. Your doctor may gradually increase your dose over several weeks up to 3600 mg per day.
      • Children—Use and dose must be determined by your doctor.
    • For Lennox-Gastaut syndrome:
      • Adults and teenagers 14 years of age and older—At first, usually 1200 milligrams (mg) per day, divided into three or four smaller doses. Your doctor may gradually increase your dose over several weeks up to 3600 mg per day.
      • Children 2 to 14 years of age—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 15 mg per kilogram (kg) of body weight per day, divided into three or four smaller doses. Your doctor may gradually increase the dose over a few weeks up to 45 mg per kg of body weight per day.
      • Children younger than 2 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions

It is very important that your doctor check the progress of you or your child at regular visits. This is necessary to allow dose adjustments and to check for serious unwanted effects.

It is important to tell your doctor if you become pregnant. Your doctor may want you to join the North American Antiepileptic Drug Pregnancy Registry, which is used by pregnant patients who are taking this medicine.

Felbamate has caused a few cases of a serious blood disorder called aplastic anemia and a few cases of liver failure. Talk to your doctor about these risks.

Stop using this medicine and check with your doctor right away if you or your child have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be symptoms of a serious liver problem.

Tell your doctor right away if you or your child has chest pain; chills; cough; fever; headache; shortness of breath; sores, ulcers, or white spots on lips or in mouth; swollen or painful glands; tightness in chest; unusual bleeding or bruising; unusual tiredness or weakness; or wheezing. These could be symptoms of aplastic anemia.

Do not stop taking felbamate without first checking with your doctor. Your doctor may want you to gradually reduce the amount you or your child are taking before stopping completely. Stopping the medicine suddenly may cause your seizures to return or to occur more often.

If you or your child develop any unusual or strange thoughts and behavior while taking this medicine, be sure to discuss it with your doctor. Other changes might be confusion, worsening of depression, hallucinations (seeing, hearing, or feeling things that are not there), suicidal thoughts, and unusual excitement, nervousness, or irritability.

Felbamate may cause blurred vision, double vision, or other changes in vision. It may also cause some people to become dizzy or drowsy. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert or able to see well. If these reactions are especially bothersome, check with your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  1. Black, tarry stools
  2. chest pain
  3. chills
  4. confusion
  5. cough
  6. delusions
  7. dementia
  8. depression
  9. fever
  10. loss of bladder control
  11. painful or difficult urination
  12. purple or red spots on the skin
  13. shakiness in the legs, arms, hands, or feet
  14. shortness of breath
  15. sore throat
  16. sores, ulcers, or white spots on the lips or in the mouth
  17. swollen glands
  18. trembling or shaking of the hands or feet
  19. unusual bleeding or bruising
  20. unusual tiredness or weakness

Less common

  1. Agitation, aggression, or other mood or mental changes
  2. bladder pain
  3. bloody or cloudy urine
  4. bone pain
  5. burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  6. clumsiness or unsteadiness
  7. frequent urge to urinate
  8. loss of appetite
  9. lower back or side pain
  10. skin rash
  11. swelling or puffiness of the face
  12. trouble with breathing
  13. unsteadiness, trembling, or other problems with muscle control or coordination

Rare

  1. Continuing headache
  2. continuing stomach pain
  3. continuing vomiting
  4. dark-colored urine
  5. general feeling of tiredness or weakness
  6. hives or itching
  7. light-colored stools
  8. muscle cramps
  9. nasal congestion
  10. nosebleeds or other unusual bruising or bleeding
  11. pain
  12. sensitivity of the skin to sunlight
  13. swollen or painful glands
  14. tightness in the chest
  15. yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Acid or sour stomach
  2. bad, unusual, or unpleasant (after) taste
  3. belching
  4. body aches or pain
  5. change in taste
  6. change in walking and balance
  7. constricted, pinpoint, or small pupils (black part of the eye)
  8. crying
  9. depersonalization
  10. diarrhea
  11. difficulty having a bowel movement (stool)
  12. difficulty with sleeping
  13. dizziness
  14. double vision
  15. dysphoria
  16. ear congestion
  17. euphoria
  18. headache
  19. heartburn
  20. hiccup
  21. indigestion
  22. loss of appetite
  23. loss of voice
  24. nausea
  25. paranoia
  26. quick to react or overreact emotionally
  27. rapidly changing moods
  28. runny nose
  29. seeing double
  30. sleepiness or unusual drowsiness
  31. sleeplessness
  32. sneezing
  33. stomach discomfort, upset, or pain
  34. trouble sleeping
  35. unable to sleep
  36. weight loss

Less common

  1. Blemishes on the skin
  2. blurred vision
  3. decreased awareness or responsiveness
  4. decreased weight
  5. difficulty with moving
  6. earache
  7. hoarseness
  8. joint pain
  9. muscle aching or cramping
  10. muscle pains or stiffness
  11. pain or tenderness around the eyes and cheekbones
  12. pimples
  13. redness or swelling in the ear
  14. severe sleepiness
  15. swollen joints
  16. tender, swollen glands in the neck
  17. trouble with swallowing
  18. voice changes

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Portions of this document last updated: March 01, 2024

Original article: https://www.mayoclinic.org/drugs-supplements/felbamate-oral-route/precautions/drg-20063811