Scratching the rash will help spread the lesions and there may be areas of rash where the skin was protected by clothing. Contrary to popular belief, the fluid from vesicles and bulla do not spread the rash. The rash can be spread from contact with fomites like shoes, clothing, tools, and from the smoke from burning plants. Animal fur can also be reservoirs of the sap and pets can help spread the antigen if they have been in contact with the plants. Topical steroids are of limited usefulness May need oral steroids for 1-2 weeks.
Some people suggest tapering doses.
Cool compresses may give some relief Oral antihistamines References Tunnessen, Walter W.Jr. The three witches of summer.