Signs and Symptoms
The most common locations for pityriasis rosea include:
- Chest
- Upper back
- Neck
- Abdomen
- Upper arms
- Thighs
In an uncommon type of pityriasis rosea, the rash may be concentrated in the armpits and groin or on the face, forearms, and shins.
Pityriasis rosea usually begins with a single patch of pink-to-red, scaly skin, from 2–5 cm in size. This "herald patch" is usually located on the trunk, neck, or upper arms. The herald patch is followed 1–3 weeks later by the development of a widespread rash, with smaller (0.5–2 cm) oval patches of pink-to-red, scaly skin on the trunk and upper arms. The second rash may form a "Christmas tree" pattern on the back.
Children sometimes have an unusual form of pityriasis rosea with lesions on the face, wrists, and legs rather than on the trunk.
Some children report feeling mildly ill (headache, stuffy nose, muscle aches) for 1–2 weeks before the herald patch forms. Additionally, some children have itching with pityriasis rosea. Becoming overheated by exercising or taking a hot shower may increase itching or make the rash more apparent.
Pityriasis rosea is a self-limited condition, meaning that it goes away on its own within 6–8 weeks even without treatment. However, the rash often leaves behind patches of lighter (hypopigmented) or darker (hyperpigmented) skin, which are more obvious in darker-skinned people and may take months to return to normal color.