clonazepam is a benzo...I know some quick acting benzos are xanax and ativan. Just ensure that you talk to your doctor about it and ensure you take it as prescribed. Just do not do it on your own!
If you need relief faster, I would suggest you ask you Psychiatrist for a script of the rapid release Clonazepam "klonopin" for breakthrough anxiety.
How are you taking it now? BID or AS NEEDED?