Dermatology Questions? Ask an Online Dermatologist.
How severe is the rash, both in distribution over the body and intensity of the reaction?
I also usually favor oral steroids when poison ivy affects the penis or scrotum.
Oral steroids are more potent and work more quickly. There are several reasons to consider using oral steroids. The most common reason would be a more severe reaction. However, it is also appropriate if a less severe reaction fails to respond to topical steroids or it affects important structures, such as the eyes or the penis. If the penis is only mildly affected, then topical treatment may be effective, but I usually prefer systemic treatment.
It is also appropriate to consider patient preference. If you wold prefer to avoid the use of prednisone, then it is reasonable to try topical treatment first, and only use the oral steroids if the topical treatment is not sufficient.
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