What is the best duration of steroid therapy for contact dermatitis (rhus)?

Scant evidence exists for the best duration of steroid therapy for contact dermatitis due to plants (rhus). Review articles recommend 10 to 21 days of treatment with topical or oral corticosteroids for moderate to severe contact dermatitis due to plants (strength of recommendation [SOR]: C, based on review articles). The primary reason given for the duration of 2 to 3 weeks is to prevent rebound dermatitis.