Asthma is the most common chronic disease of childhood, affecting an estimated 155 million individuals in the world. The cost
of treating the disease in the United States is approx 6 billion dollars per annum ( < cite > 1 < /cite > ). More than half of this expense is spent on hospital care and 80 most treatment ( < cite > 1 < /cite > ). The market to the pharmaceutical industry for asthma medication is6 billion dollars per annum (1). More than half of this expense is spent on hospital care and 80% is attributable to the 20% of patients who require the
most treatment (1). The market to the pharmaceutical industry for asthma medication is 5.5 billion per annum (2).