How long can the rash of slapped cheek disease last?

Slapped cheek: Slapped cheek is the first stage of 5th disease, which is a common viral infection of childhood and lasts 2-5 days, then a lacelike rash begins on the arms. The rash can recur because of heat or exercise over weeks/months after the initial rash fades. The infection is self limited and no treatment is necessary, but if your child seems sick, always best to see your pediatrician.