Allergy checker

Hey all!
I love my Palm TX, and use it every day. I got Thompson (the hospital provided), Epocrates and - the best - the IVDH 9 on it (for IV drugs). I am working in the ER, and there is a question that comes up frequently. What about allergies? I know that a patient that is allergic to PCN shound't receive Zosyn, but I am sure there are more drugs out there. So, I am looking for a program where I can plug in an allergy and see if I can give the med that I am supposed to give. Any suggestions??? Thanks so much!