Causes
Pityriasis rosea is not triggered by an allergic reaction to food or medication or by stress.
The signs, immediately before the onset, resemble those caused by a viral infection. Human beta Herpes Virus ( HHV-7), has now been associated with the disease. This virus is believed to be genetically linked to Cytomegalovirus. It may affect more than one person in a family at a time, yet the disease is not considered contagious.