Oral glucocorticoids for acute exacerbations
In treating acute exacerbations, both oral and parenteral glucocorticosteroids (GCSs) are equally effective. Unless your patient is moribund, prednisone will work just as quickly and as well as equivalent parenteral doses of hydrocortisone or methylpred-nisolone. In managing mild to moderate exacerbations of asthma in family practice, 0.6 mg/kg/d as a single morning dose for 10 to 14 days without tapering will maximize airway calibre without causing adrenal suppression.’,
For adults, experts generally recommend maximizing airway calibre (and lung function) with this dose and duration of treatment rather than with lower doses or the same dose for a shorter period. Webb has clearly shown that it takes 10 days, and this dose, to maximize expiratory flow rates and that this approach is likely to produce longer periods between relapses. How frequently one can give this treatment course without causing osteoporosis or other problems is unknown. One should probably be aiming for repeat administration not more than every 12 weeks.
Recent research reinforcing the notion that prednisone dosage does not need to be tapered was obtained from patients using inhaled glucocorticosteroid concurrently, and this practice is recommended. Prior recommendations included stopping inhaled GCS during oral GCS treatment. This practice seems to have been based on several concerns:
- • concerns about administering excessive total doses of glucocorticosteroid, which is not really an issue given the low systemic bioavailability of inhaled GCS;
- • concern that the vehicle in pressurized metered dose inhaler steroids could cause increased cough and bronchoconstriction during exacerbations; if one uses a dry powder device, this issue no longer arises; and
- • concern over cost. The small additional cost seems outweighed by such benefits as encouraging overall compliance and reducing risk of exacerbations when oral prednisone doses are tapered. The role of nebulized GCS remains unclear and is beyond the scope of this article.
Inhaled glucocorticosteroids are currently key to asthma management. Although there have been concerns about the safety of inhaled GCSs in the long-term, available evidence suggests that the newer agents are safe at doses below 2000 µg/d. As cost is an important issue in mild to moderate asthma, one can use beclomethasone or budesonide interchangeably, but the choice of the delivery device is important.
For more severe asthma, my current recommendation is to use budesonide via a Turbuhaler®, a combination that guarantees drug delivery as well as lowest possible systemic bioavailability and that has proven clinical efficacy. Glucocorticosteroids are by no means a cure, as symptoms recur soon after discontinuation in most patients. Thus, we must encourage new avenues of asthma management: for example, emphasis on primary prevention of asthma in at-risk newborns (offspring of atopic parents). For this group encouragement of breastfeeding and avoidance of exposure to house dust mites, animal dander, and environmental tobacco smoke in the first few months of life could reduce the subsequent incidence of atopy and asthma. ■