What equine calmer to use?

My mare goes Absolutely crazy at shows. Which is a shame because she has awesome speed and would make a great barrel horse! What i have been doing lately, is taking her to arena's and riding her around when no one is there, i also have been riding her in a group thingy at my fair grounds and she is getting alot better! I hope my new show mare doesnt do the same! (: goood luck!