I have a severe case of poison sumac/ivy/or oak and i'm treating it with steroids--is this standard?

If its bad -then yes: Most poison ivy is a contact dermatitis - that means there is a local reaction to the oil where it touches your skin. However, some people actually have a true allergic reaction as well - where many things in the body happen and release chemicals in the body causing the more severe reactions. If usual anti-allergy things don't work (ie antihistamines, etc), then steroids are used to settle things.