Pityriasis Rosea is a common, self-limiting skin condition , usually seen in young adults. It is believed to be related to a viral infection (possibly human herpes virus 6 or 7), though it is not contagious in the usual sense. Key Features 1. Initial Lesion (Herald Patch) A single, round or oval “herald patch” appears first. Usually on trunk, 2–10 cm in size. Pink or salmon-colored with fine scaling at the edges. 2. Generalized Rash Within 1–2 weeks, multiple smaller oval patches appear. Distributed mainly on the trunk and proximal limbs in a “Christmas tree pattern” along skin cleavage lines. Lesions may itch (mild to moderate). 3. Duration Self-resolves within 6–8 weeks , sometimes up to 12 weeks. Differential Diagnosis Tinea corporis (ringworm) – but lacks central clearing and fungal hyphae. Secondary syphilis – must be ruled out (especially if palms/soles involved). Drug eruption . Psoriasis (guttate type) . Nummular ecz...