Klonopin (clonazepam) is a medication commonly used to treat bipolar disorder. It is prescribed to control mania and can be used instead of lithium. Potential side effects include weakness, drowsiness, nausea, and changes in appetite or mood. It is important for patients taking Klonopin to monitor for toxicity and drug interactions and notify their doctor of any severe or unusual symptoms. Klonopin requires a prescription and doctor supervision for safe and effective treatment of bipolar disorder.