Classically, pityriasis rosea begins as an erythematous, scaly patch on the trunk, known as a herald patch. This large lesion is commonly 2–10 cm in diameter, ovoid, erythematous and slightly raised, ... What is pityriasis rosea?

Understanding the Context

Pityriasis rosea is a self-limiting rash, which resolves in about 6–10 weeks. It is characterised by a large circular or oval "herald patch", usually found on the chest, abdomen, or back. Pityriasis rosea typically begins with an oval, slightly raised, scaly patch — called the herald patch — on the face, back, chest or abdomen. Before the herald patch appears, some people have headache, fatigue, fever or sore throat.

Key Insights

Pityriasis rosea starts with a single patch on your back or torso. That’s called the “herald patch” or “mother patch.” It’s usually oval-shaped and about 2-10 centimeters (a little less... Pityriasis rosea is a common rash that often starts with a large red or pink patch called a herald patch. The rash is not contagious and usually goes away on its own within six to eight weeks. People with deeply pigmented skin often see a herald patch (usually gray, violet, or brown) and small bumps appear at the same time (B).

Final Thoughts

For a few days to 2 weeks, the herald patch may be the only sign of pityriasis rosea on your skin. Pityriasis rosea is a type of skin rash. It is also called Christmas tree rash. It starts with 1 large, scaly patch. It may be round or oval. This is called the herald patch.

It then causes many more small patches. The rash most often appears on the chest, back, and belly. It can take 1 to 3 months to go away. Symptoms of Pityriasis Rosea Pityriasis rosea at first causes a single rose-colored or tan-colored round patch of skin about 1 to 4 inches (2 to 10 centimeters) in diameter.