Is Clonazepam Better Than Alprazolam For Controlling Anxiety?

I have generalized anxiety disorder and have been prescribed alprazolam .25 mg bid as needed as well as Lexapro 20 mg. I rarely was taking the alprazolam until the last month when I have been experiencing panic attacks with nausea, heart racing, feeling like I am going crazy etc. I am a counselor in a high stress environment. I do not have a history of addiction. I am wondering is clonazepam would be a better anti anxiety agent or raising the dose of alprazolam?