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Uses

What is clobazam used for?

Clobazam is commonly used to treat seizures associated with a certain type of epilepsy called Lennox-Gastaut syndrome (LGS).

Clobazam may also be used for other conditions as determined by your healthcare provider.

How does clobazam work (mechanism of action)?

Clobazam produces a calming effect on the brain and nerves, which helps to prevent seizures.

How is clobazam supplied (dosage forms)?

Brands and other names

  • Onfi
  • Sympazan

Dosage forms and strengths

  • 5 mg, 10 mg, 20 mg oral films
  • 2.5 mg/mL oral suspension
  • 5 mg, 10 mg, 20 mg oral tablets

How should I store clobazam?

Oral Tablet and Oral Film. Clobazam should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C) for shorter periods of time, such as when transporting it. Store in a cool, dry place.

Oral Suspension. Store clobazam oral suspension in its original bottle in an upright position. After the bottle has been opened for 90 days, discard any leftover medicine you do not use.

Side Effects

What are the most common side effects of clobazam?

The most common side effects of clobazam are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Constipation
  • Drowsiness (or sleepiness)
  • Fever
  • Lack of energy
  • Drooling

There may be other side effects of clobazam that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of clobazam?

While less common, the most serious side effects of clobazam are described below, along with what to do if they happen.

Severe Allergic Reactions. Clobazam can cause allergic reactions, including a specific type of allergic reaction called DRESS. DRESS stands for Drug Reaction with Eosinophilia and Systemic Symptoms. It is also sometimes called multiorgan hypersensitivity. This is a reaction that can affect multiple parts of the body, including your liver, kidneys, and heart. Stop taking the medicine and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain
  • Dark colored urine
  • Your skin or the whites of your eyes turning yellowish in color (also called jaundice)

Severe Skin Reactions. Clobazam can cause severe skin reactions called Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) that can lead to death if not treated. If you develop a rash, stop clobazam and call your healthcare provider right away. Get emergency help right away if you have any of the following symptoms of SJS or TEN.

  • Painful red or purple skin that looks burned and peels off
  • Flat red rash or blisters on your skin, mouth, nose, and genitals
  • Red, painful, watery eyes

Suicidal Thoughts and Actions. Clobazam may cause suicidal thoughts or actions in a small number of people. If you are about to harm yourself, call 911 or call or text 988, the Suicide & Crisis Lifeline. Call your healthcare provider right away if you have any of the following symptoms.

  • New or increased thoughts of suicide or death
  • Suicide attempt
  • New or increased feelings of anxiety, depression, or other unusual changes in mood or behavior 

Risk of Misuse and Addiction. Misusing clobazam can lead to serious side effects like coma or death. Misuse means taking a medicine in a way other than how it was prescribed. Take clobazam exactly as prescribed. Tell your healthcare provider if you feel that clobazam is not working. Call your healthcare provider right away or go to the nearest emergency room if you experience any of the following serious symptoms.

  • Sudden confusion or feeling disoriented
  • Feeling paranoid
  • Suicidal thoughts or actions
  • Seizures
  • Trouble breathing

Dependence and Withdrawal Reactions. Clobazam can cause physical dependence, which means your body relies on the medicine to function properly. If you stop clobazam suddenly, it could lead to withdrawal symptoms, which may be life-threatening. Do not stop taking clobazam without talking with your healthcare provider. Your healthcare provider will tell you how to stop clobazam to reduce the risk of withdrawal reactions. Call your healthcare provider right away or go to the nearest emergency room if you experience any of the following serious symptoms.

  • Unusual movements, responses, or expressions
  • Seizures
  • Sudden and severe mental or nervous system changes
  • Seeing or hearing things that others do not see or hear, also called hallucinations
  • An extreme increase in activity or talking
  • Losing touch with reality

Some people may experience the following symptoms of a withdrawal reaction that can last for several weeks to more than 12 months.

  • Anxiety
  • Trouble remembering, learning, or concentrating
  • Depression
  • Problems sleeping
  • Feeling like insects are crawling under the skin
  • Weakness
  • Shaking
  • Muscle twitching
  • Burning or prickling feeling in the hands, arms, legs, or feet
  • Ringing in the ears

Risk With Opioid Medicines. Taking clobazam with an opioid medicine, such as codeine, morphine, and oxycodone, may lead to severe drowsiness, breathing problems, coma, and death. Get emergency help right away if you experience the following symptoms.

  • Slow or shallow breathing
  • Breathing stops (which may lead to the heart stopping)
  • Excessive sleepiness or trouble staying awake 

Decreased Alertness or Coordination. Clobazam can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how clobazam affects you.

Warnings & Precautions

Who should not use clobazam?

Allergies to Ingredients. People who are allergic to any of the following should not take clobazam.

  • Clobazam
  • Onfi
  • Sympazan
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific clobazam products they stock.

What should I know about clobazam before using it?

Do not take clobazam unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share clobazam with other people, even if they have the same condition as you. It may harm them.

Keep clobazam out of the reach of children. Clobazam is a controlled substance because it can be misused or lead to dependence. Store clobazam in a safe place to protect it from theft. It is illegal to sell or give away this medicine.

Clobazam can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how clobazam affects you.

Oral Films. Place the entire clobazam oral film on top of your tongue. The film will dissolve on its own. You can swallow your saliva normally, but avoid chewing, spitting, or talking until the film dissolves. Do not drink liquids at the same time as taking clobazam oral film.

Oral Suspension. Shake the bottle well before you take each dose. Use the syringe that comes with your medicine to draw up your dose, then slowly squirt the medicine into the corner of your mouth. A household spoon is not an accurate measuring device and may cause you to take the wrong dose. A patient instruction sheet is enclosed in your medicine container to show you how to use the oral syringe.

Oral Tablets. Clobazam oral tablets may be swallowed whole or broken in half along the score. If you cannot swallow the tablets whole, they may be crushed and mixed with applesauce.

What should I tell my healthcare provider before using clobazam?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if clobazam is right for you.

In particular, make sure that you discuss any of the following.

Mental Health Problems. Tell your healthcare provider about your recent and current mental health problems, especially if you have had depression, thoughts of suicide or dying, or have ever attempted suicide.

Substance Use Disorder. Clobazam is a controlled substance and may be misused or lead to dependence. Tell your healthcare provider if you have a history of a drug or alcohol disorder. 

Current and Past Health Conditions. Tell your healthcare provider if you have any of the following.

  • Liver problems
  • Kidney problems
  • Lung problems

Other Medicines and Supplements. Clobazam may interact with other medicines and supplements. Before using clobazam, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how clobazam could affect pregnancy or harm an unborn baby. Taking clobazam during the later stages of pregnancy can cause withdrawal and the following symptoms in newborns.

  • Breathing problems
  • Sluggish
  • Low muscle tone
  • Jittery
  • Fussiness or irritability
  • Restlessness
  • Shaking
  • Excessive crying
  • Feeding problems

Tell your healthcare provider if you are or plan to become pregnant. Your healthcare provider will advise you if you should take clobazam while you are pregnant or trying to get pregnant. If you become pregnant while using clobazam, talk to your healthcare provider about registering with the North American Antiepileptic Drug Pregnancy Registry. This registry collects information about the safety of antiepileptic medicines during pregnancy. You can register by calling 888-233-2334 or online at www.aedpregnancyregistry.org. 

Breastfeeding. Clobazam passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should take clobazam while breastfeeding.

Interactions

Does clobazam interact with foods or drinks?

There are no known interactions between clobazam and foods or drinks.

Do not drink alcohol while taking clobazam. The risk of serious problems such as severe dizziness, sleepiness, and trouble breathing may be increased if you drink alcohol while taking clobazam.

Does clobazam interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. 

In particular, make sure to discuss if you are using any of the following before taking clobazam.

  • An opioid, such as oxycodone, morphine, codeine, or fentanyl, which is a medicine used for certain types of pain
  • Any other medicine that causes dizziness and sleepiness, such as prescription pain medicines, sleep medicines, and medicines for anxiety
  • A birth control pill or hormonal contraceptive medicine
  • Fluconazole (Diflucan), which is a medicine to treat fungal infections
  • Omeprazole (Prilosec), which is a medicine for certain stomach and esophagus problems (such as acid reflux, ulcers)
  • Fluvoxamine (Luvox), which is a medicine commonly used to treat obsessive-compulsive disorder (OCD)
  • Flumazenil (Romazicon), which is a medicine used to manage benzodiazepine overdose

Some other medicines may alter the blood levels of clobazam. Tell your healthcare provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with clobazam. Always check with your healthcare provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much clobazam?

If you or someone else has used too much clobazam, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of clobazam?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.