Klonopin is a group of medications. It is used for anxiety and panic disorder. It is a category class of drugs. known as benzodiazepines clonazepam is a fast-acting Medicine. It calms your nervous system. It can create feelings of relaxation. Klonopin side effects may include drowsiness, dizziness, feeling tired, depressed, etc. Klonopin is available in 1mg and 2mg.