Klonopin is a brand name. It is an oral tablet It Treats Anxiety panic disorder and agoraphobia. Klonopin contains the active drug clonazepam and belongs to the benzodiazepine drug class. Klonopin is FDA-approved to treat: Certain seizure disorders in adults and children of all ages It works by calming your nerves. Take This medicine By mouth as directed. It can create feelings of relaxation. Klonopin side effects can include drowsiness, Dizziness, Agitation, and Confusion. Klonopin Is available in 1mg and 2mg.