Clobazam has a risk for abuse and addiction, which can lead to overdose and death. Taking this medication with alcohol or other drugs that can cause drowsiness or breathing problems (especially opioid medications such as codeine, hydrocodone) may cause very serious side effects, including death. To lower your risk, your doctor should have you take the smallest dose of clobazam that works, and take it for the shortest possible time. Be sure you know how to take clobazam and what other drugs you should avoid taking with it. Get medical help right away if any of these very serious side effects occur: slow/shallow breathing, unusual lightheadedness, severe drowsiness/dizziness, difficulty waking up. Suddenly stopping this medication may cause serious (possibly fatal) withdrawal, especially if you have used it for a long time or in high doses. To prevent withdrawal, your doctor may lower your dose slowly. Tell your doctor or pharmacist right away if you have any withdrawal symptoms such as headaches, trouble sleeping, restlessness, hallucinations/confusion, depression, nausea, or seizures. Withdrawal symptoms may sometimes last weeks to months.

Drowsiness, dizziness, tiredness, headache, constipation, weight gain, cough, drooling, trouble sleeping, or nausea may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: mental/mood/behavior changes (such as agitation, nervousness, confusion, memory loss), muscle weakness, loss of coordination, shaking (tremor) of the fingers, vision changes (such as blurred vision, double vision), trouble speaking, painful urination. A small number of people who take anticonvulsants for any condition may experience depression, suicidal thoughts/attempts, or other mental/mood problems. Tell your doctor right away if you or your family/caregiver notice any unusual/sudden changes in your mood, thoughts, or behavior including signs of depression, suicidal thoughts/attempts, thoughts about harming yourself. Get medical help right away if you have any very serious side effects, including: slow/shallow breathing. Clobazam may rarely cause very serious (possibly fatal) skin reactions, especially during the first 8 weeks of treatment or when restarting treatment with this medication. Get medical help right away if you develop any of the following symptoms: skin rash/blisters/peeling, itching, or mouth sores. If you have a very serious skin reaction and your doctor says it was caused by clobazam, you should not take the medication again. Ask your doctor or pharmacist for more details. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: fever, swollen lymph nodes, rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Some products that may interact with this drug include: orlistat, sodium oxybate. Other medications can affect the removal of clobazam from your body, which may affect how clobazam works. Examples include fluconazole, fluvoxamine, among others. The risk of serious side effects (such as slow/shallow breathing, severe drowsiness/dizziness) may be increased if this medication is taken with other products that may also cause drowsiness or breathing problems. Tell your doctor or pharmacist if you are taking other products such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine). Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely. This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use reliable backup birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.