Asthma is the most common chronic disease of children. A short (3-5 day) course of a short-acting steroid such as Prednisone or Prednisolone has long been the standard of care for asthma exacerbation. Dexamethasone efficacy in asthma exacerbation has been studied in the outpatient setting and was found to be as effective as Prednisone. Dexamethasone has the advantage of shorter course, more compliance, and more tolerable. This has led many emergency departments to provide a 1-2 dose course of Dexamethasone on discharge. Thus, many inpatients have received a first dose of Dexamethasone prior to reaching the inpatient unit, leading to confusion about the best plan for these patients. Many hospitalist pediatricians continue to give a 5-day total course with Prednisone, but some patients have begun to receive a second dose of Dexamethasone 24 hours after the first dose. To our knowledge, no studies have been done to compare the efficacy of these two protocols in pediatric patients requiring hospitalization. The hypothesis is that a second dose of Dexamethasone is as effective as four additional days of Prednisone in hospitalized children with asthma exacerbation. This is an open label, randomized control study comparing these treatments in children age 2-18 hospitalized with asthma exacerbation who have received a first dose of Dexamethasone.