### What is Pityriasis Rosea? Pityriasis rosea is a common, harmless skin condition that causes a rash. It usually appears on the torso, upper arms, thighs, or neck. The rash often starts with a single large patch known as the “herald patch” or “mother patch,” which is oval-shaped and can be 2-10 centimeters in diameter. A week or two later, smaller “daughter patches” may appear, often forming a pattern that resembles a Christmas tree. ### Symptoms - **Herald Patch**: A single, large, oval-shaped patch - **Daughter Patches**: Smaller, scaly rashes - **Itching**: Especially when exercising or exposed to heat - **Other Symptoms**: Headache, fever, sore throat ### Causes The exact cause of pityriasis rosea is unknown, but it is believed to be related to viral infections, possibly certain strains of the herpes virus. It is not contagious and usually affects children, teens, and young adults. ### Diagnosis A dermatologist can usually diagnose pityriasis rosea by sight. To confirm, they may order a blood test, skin scraping, or biopsy to rule out other conditions like eczema, ringworm, or psoriasis. ### Treatment While pityriasis rosea usually goes away on its own within 6-8 weeks, treatments can help soothe symptoms: - **Antihistamines**: To ease itching - **Corticosteroids**: Creams for dryness, scaling, and itching - **Over-the-counter Topicals**: Calamine lotion or zinc oxide - **Prednisone**: An oral steroid for severe itching - **Acyclovir**: An antiviral medication that may help the rash go away sooner ### Home Remedies - **Oatmeal Baths**: To soothe itching - **Anti-inflammatory Diet**: Some believe it can help lessen itching ### When to See a Doctor If the rash lasts longer than 3 months or if you are pregnant, consult a doctor. Pregnant women may have a higher risk of complications. ### Prognosis Pityriasis rosea is generally harmless and does not return once it goes away. In some cases, it may leave temporary patches of darker or lighter skin, especially in people with darker skin tones.