Clobazam (Onfi)

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Clobazam (kloe BA zam) is the generic name for Onfi® (ON fee).This medicine is used to control seizures. It works by affecting natural chemicals in the brain.


  • A child who is allergic to clobazam should not take this medicine.
  • Tolerance (your body gets used to this medicine) can develop. Check with your doctor if you feel it is not working anymore.
  • If a patient thinks she might be pregnant, she should tell the doctor before she begins taking this or any medicine. This medicine may cause problems such as birth defects if taken during pregnancy. It may also cause possible withdrawal symptoms for the infant after birth. If a patient is breastfeeding her baby, she should tell her doctor before she begins taking this or any medicine. This medicine can pass into breast milk and cause side effects in the baby.

How to Give This Medicine

  • Read the label carefully and make sure you are giving your child the right dose. Shake this medicine before using it.
  • Use a pediatric measuring device (available at the pharmacy) to measure the exact dose. Do not measure liquid medicines in kitchen spoons.
  • Tablets may be chewed, dissolved in liquid, or swallowed whole. Stay with your child until they have swallowed the dose of medicine.
  • It is very important to give the medicine every day as ordered, even if your child is feeling fine. Do not change doses or stop the medicine without talking to your child’s doctor.
  • It is important to keep a record of when the medicine is given. 

If You Forget to Give a Dose

  • If you miss a dose of this medicine, give it as soon as you remember. If it is almost time for the next dose, do not give the missed dose at all and do not double the next dose. Instead, go back to your regular dosing schedule. If you have any questions about this, check with your child's doctor or pharmacist.
  • Do not give two doses of medicine closer than six hours apart.
  • Missing one dose of medicine or giving it late once in a while will not cause a seizure in most children, but some children may be more sensitive to this. Missing several doses of this medicine is likely to cause a seizure.

If a Dose Is Vomited

  • If your child gags or chokes and spits out the dose before swallowing it, let the child calm down. Then give the same amount one more time.
  • If your child vomits within 15 minutes of taking his medicine, you can repeat the dose one time.
  • If they vomit again, do not give any more medicine. Wait until the next scheduled dose and try again.
  • If they vomit and it has been 15 minutes since they took the medicine, do not give any more medicine. The medicine has already been absorbed in the body.

Medicine Storage

  • Store all medicine out of the reach of children.
  • Always keep medicine in the original bottle from the pharmacy.
  • Keep this medicine away from heat or direct sunlight.
  • Do not use this medicine after the expiration date printed on the container.
  • When your child’s doctor decides this medicine is no longer needed, discard the medicine in the correct way. Dissolve it in water or rubbing alcohol and mix it in used coffee grounds or kitty litter. Throw this mixture in the trash.

Drug and Nutrient Interactions

  • Taking this medicine with alcohol can cause drowsiness and can be dangerous. Some cold medicines, cough syrups and mouthwashes contain alcohol. Check with your doctor or pharmacist before giving over-the-counter medicines because taking this medicine with alcohol can cause drowsiness and can be dangerous.
  • Clobazam may be affected by other drugs. Ask your doctor and pharmacist before starting any new medicine. This is true whether the medicine requires a prescription or it can be bought without a prescription.

Possible Side Effects

  • Drowsiness
  • Drooling
  • Nausea (upset stomach)
  • Unsteady walk
  • Constipation
  • Rash
  • Behavior problems
  • Trouble with vision

What to Do About Side Effects

  • If a skin rash occurs, stop giving the medicine and call your child's doctor.
  • If your child becomes drowsy or sleepy, do not let them ride a bike or operate machinery (such as a lawnmower or car), or take part in any activities where they must stay alert and awake.

When to Call the Doctor

If your child is having any side effects that continue or are very bothersome, call the doctor.


Call for emergency help if your child has any of these signs of an allergic reaction:

  • Trouble breathing
  • Swelling of the tongue
  • Swelling of hands, feet, or ankles.


  • Ask your pharmacist for two labeled bottles if your daycare provider will be giving this medicine.
  • Get this prescription refilled at least 5 days before the last dose is given. This is very important. This gives you a few days in case there is a problem with refills available, insurance coverage, or if the pharmacy has to order the medicine.
  • Some pharmacies may not have this medicine. Please ask your nurse to call your pharmacy before you leave the hospital to see if they have or can order this medicine for you. You may also have the prescription filled at the Nationwide Children's Outpatient Pharmacies.

Other Information

  • Tell your child's doctor and pharmacist if they have a strange or allergic reaction to any medicine.
  • Bring all your child's medicines with you in the original bottles whenever they see a doctor, go to an emergency room, or are admitted to the hospital. 
  • Learn the name, spelling, and dose of this medicine. Also, teach your child if they are old enough.
  • If your child takes too much of this medicine, or if someone else takes this medicine, call the Central Ohio Poison Center at 1-800-222-1222 (TTY 614-228-2272). They will tell you what to do. 
  • Your child should wear a medical ID bracelet or necklace. In an emergency, a doctor will need to know that your child is taking this medicine.
  • When your child goes to the dentist, be sure to tell the dentist that the child is taking this medicine and why.
  • Tell your child's teacher, school nurse, coach, babysitter, and others that your child is taking this medicine and what side effects to watch for.
  • Your child's school will need a note from you and from the doctor if the medicine is to be given at school by the school nurse.
  • Do not stop giving this medicine or change the amount given without first talking with your child’s doctor or pharmacist.
  • The doctor has prescribed this medicine for your child only. Do not give it to anyone else.

If you have any questions, be sure to ask your doctor, nurse, or pharmacist.

Clobazam (PDF)

HH-V-253 9/13, Revised 8/19 | Copyright 2013, Nationwide Children’s Hospital