Clobazam (By mouth)

Clobazam (KLOE-ba-zam)

Treats seizures from Lennox-Gastaut syndrome. This medicine is a benzodiazepine.

Brand Name(s):

Onfi, Sympazan

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to clobazam.

How to Use This Medicine:

Thin Sheet, Liquid, Tablet

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
  • Film: Place the whole film on top of your tongue. Do not take any liquid when using this medicine. Do not chew, spit, or talk while the film dissolves. If you need a second film, wait until the first film dissolves before using a second film.
  • Oral liquid: Shake the bottle just before each dose. Use the bottle adapter and dosing syringe in the package to measure the right dose. Squirt the right amount of medicine directly into the corner of the mouth. Wash the syringe, barrel, and plunger after each use, and allow the parts to air dry. Do not put the syringe in the dishwasher.
  • Tablet: You may swallow the tablet whole, break it in half along the score, or crush and mix it in applesauce.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Store the bottle upright and with the adapter in place. Throw away any unused oral liquid 90 days after you open the bottle.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can affect how clobazam works. Tell your doctor if you are using any of the following:
    • Cannabidiol, dextromethorphan, fluconazole, fluvoxamine, midazolam, omeprazole, ticlopidine
    • Birth control pills
    • Medicine to treat depression
    • Narcotic pain medicine
  • Do not drink alcohol while you are using this medicine.
  • Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or planning to become pregnant. Using this medicine during the later part of a pregnancy may cause problems in your newborn baby (including sedation or withdrawal symptoms). Tell your doctor right away if you think you have become pregnant.
  • Tell your doctor if you are breastfeeding or planning to breastfeed. This medicine passes into your breast milk and may cause problems in your baby. Talk to your doctor about the best way to feed your baby.
  • Tell your doctor if you have kidney disease, liver disease, lung disease or breathing problems, or a history of alcohol or drug abuse, depression, or a mood disorder.
  • This medicine may cause the following problems:
    • Increased risk of overdose, which can be life-threatening
    • Respiratory depression (serious breathing problem that can be life-threatening), when used with narcotic pain medicines
    • Serious skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis
    • Drug reaction with eosinophilia and systemic symptoms (DRESS)
  • This medicine can increase thoughts of suicide. Tell your doctor right away if you start to feel depressed and have thoughts about hurting yourself.
  • Birth control pills may not work as well when used with this medicine. Use a second form of birth control to keep from getting pregnant and for 28 days after your last dose.
  • This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
  • Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely. Your seizures may return or occur more often if you stop using this medicine suddenly.
  • This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, red skin rash
  • Blue lips, fingernails, or skin
  • Blurred vision, change or loss of consciousness, lightheadedness, dizziness, or fainting, problems with coordination or walking, unusual drowsiness or sleepiness
  • Confusion or unusual excitement, nervousness, irritability
  • Depression, anxiety, irritability, hallucinations, trouble sleeping, unusual behavior, thoughts of hurting yourself or others
  • Extreme tiredness or weakness, slow heartbeat, trouble breathing

If you notice these less serious side effects, talk with your doctor:

  • Constipation
  • Drooling

If you notice other side effects that you think are caused by this medicine, tell your doctor

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


Last Updated: 9/6/2024

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