Clonazepam 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 clonazepam that works, and take it for the shortest possible time. Be sure you know how to take clonazepam 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, loss of coordination, or increased saliva production 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. A small number of people who take anticonvulsants for any condition (such as seizures, bipolar disorder, pain) 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: confusion, memory problems, signs of depression, suicidal thoughts/attempts, thoughts about harming yourself. 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: 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. 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.