I Have Many Allergies. Sometimes If I Touch The Wrong

Question: I have many allergies. Sometimes if I touch the wrong food, blisters pop out all over my hands. Naturally, I try to avoid touching things I think will cause this reaction but it's impossible to be perfect. Is there any OVER-THE-COUNTER cream or med I can buy that will alleviate this problem. Also, at work, when I eat in the cafeteria, sometimes I have bad reactions to the food. About one hour after I eat, I get severe muscle spasms that last one or two hours. Oatmeal, for instance, will do it. I've eaten oatmeal at restaurants before and never had this reaction. They must put something in the oatmeal. Other foods do this also like cokes, other carbonated drinks, and sweet pastries. I do try to avoid these foods but again, is there anything I can buy at a pharmacy that might help?