Does herytema migrans go away if treated with cortisone?

Erythema migrans: Cortisone makes a lot of rashes decrease or resolve, but does not treat the underlying cause unless allergic reaction(dermatitis) . One should identify the cause of erythema migrans since Lyme/STARI -Southern tick associated rash/ illness disease is a possibility with significant complications and it is critical to get appropriate antibiotic therapy f/u/ w/ doc.