Inclusion Criteria:

• * Age 6 to less than 21 years at the enrollment visit
• * Physician diagnosis of asthma
• * History of an asthma exacerbation in the previous 12 months, defined as either:
• * Treatment with systemic corticosteroids, or
• * Increase in rescue medication use (i.e., albuterol or inhaled corticosteroid) for 24 hours or more, or
• * One or more missed school days due to asthma symptoms, or
• * An unscheduled visit for asthma at either a physician's office, urgent care, hospital emergency room, or
• * Hospitalization for asthma

Exclusion Criteria:

• * Previous allergic reaction to systemic corticosteroids
• * Hepatic, biliary, or renal disease that can interfere with drug metabolism/excretion
• * Chronic medical disorders that may increase the risk of drug-related injury, including osteogenesis imperfecta (increased risk of fracture with corticosteroids), or Crohn's disease, ulcerative colitis, juvenile rheumatoid arthritis, clotting disorders, or Factor deficiency (increased risk of bleeding with corticosteroid therapy)
• * Pregnancy
• * Current smoking
• * Congenital disorders or deformities of the chest wall, lungs or airways
• * History of premature birth \<35 weeks gestation
• * Unwillingness to receive triamcinolone
• * Planning to relocate before study completion