Systemic steroids will act directly upon the bloodstream rather than just the lungs. Prednisone and other systemic steroids are fast acting and take about 12 hours to be affective. Prednisone will be used sparingly. It will be used in combination with other medications to control sudden and severe symptoms where the patient will be given high dosages of prednisone for a few days. This is called a steroid burst, which is often necessary in order to control the symptoms. Systemic drugs may also be given in low dosages every other day when asthma symptoms are chronic or very hard to control.
A recent meta-analysis undertaken for the National Asthma Campaign in preparation for the revised Asthma Management Handbook showed that combination therapy with an inhaled corticosteroid and a long-acting beta agonist achieved statistically greater improvements in lung function tests than inhaled corticosteroids alone in patients aged 4-80 years who had previously not received corticosteroids. These improvements may not always be of clinical importance, but combination therapy also resulted in fewer exacerbations in patients who were symptomatic on inhaled corticosteroids alone.