Question: how long does it take for prednisone to clear rash?
Answer: Prescribe oral steroids for severe cases Since the painful itchy blisters and erythema from the oleoresin may take up to 1 week to appear, and because the rash may persist for more than 2 weeks, it makes sense to prescribe oral steroids in severe cases for longer than the usual 5- to 7-day burst.