Taking clonazepam with opioid medications (such as codeine, hydrocodone) may increase your risk of 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. 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.
Clonazepam is used to prevent and control seizures. This medication is known as an anticonvulsant or antiepileptic drug. It is also used to treat panic attacks. Clonazepam works by calming your brain and nerves. It belongs to a class of drugs called benzodiazepines.