Because the disease has seasonal episodes, the rash is self-limiting, rarely recurring, and the initial onset is a prodromal spot, and we have not found any definite allergic substances causing the disease, so most of them are thought to be related to viral infections.

Recently, Song Fuxiang and others studied the relationship between pityriasis rosea and coxsackie group B virus infection, and the results of the study showed that the positivity rate of serum coxsackie group B virus specific IgM in patients with pityriasis rosea in the acute stage was significantly higher than that of healthy controls, and the content of circulating immune complexes of serum was significantly higher in acute than that in the recovery stage, and the neutralization test and viral isolation proved that there were coxsackie group B virus infections in the body of the patients, and these results suggested that the pathogenesis of pityriasis rosea is not easy to be determined. These results suggest a direct relationship between the development of pityriasis rosea and coxsackie group B virus infection.

Additionally fungal, bacterial infections or other microorganisms, such as spirochetes, have not been proven to be the source of the disease. It is also thought to be an allergic diagnosis of some infection or a cutaneous manifestation of gastrointestinal toxicity.

The natural course of pityriasis rosea is about 6-8 weeks. It may resolve spontaneously. Rash occurs in the trunk and proximal extremities, typical rash such as coin-sized red spots, surrounded by a little flakes. After the rash is fully developed, it slowly subsides! There are usually no conscious symptoms! You can take Banlangen. If it is itchy, take paracetamol. Go to the hospital for ultraviolet radiation to speed up the rash. (Advice for reference)