Have you tried more natural options?
I used to have really high levels of anxiety when I was younger, causing me to stutter, making me even more anxious. If you know what triggers your anxiety (in my case public speaking) I recommend chewing 3 Suntheanine tablets (link below) 15 minutes before the event (or whatever triggers your anxiety), the effect usually last about 1-2 hours.
Suntheanine helps break the "mental loop" that causes anxiety. Suntheanine is not a drug is more like a "helper" to make things easier while your mind "gets used" to what triggers the anxiety.
If you decide to try sunthenine try the "chewable" version since that one works the best (link bellow).
Good Luck!
http://www.amazon.com/Natural-Factor...ds=suntheanine