You are currently viewing Acute Asthma: Single-Dose Dexamethasone vs. 5-Day Prednisone

Daniel J. Pallin, MD, MPH reviewing Rehrer MW et al. Ann Emerg Med 2016 Apr 22.

Routine management of asthma exacerbations in emergency department patients includes a 5-day course of prednisone. Dexamethasone has a longer half-life, and prior research has suggested that a

1­ or 2­day course of dexamethasone might be as good as a 5-day course of prednisone. Investigators randomized adults with mild-to-moderate acute asthma exacerbations to a single 12­mg dose of oral dexamethasone or 5 days of 60­mg prednisone daily. Of 465 adult patients randomized, 376 completed the protocol and were analyzed. As assessed by telephone follow-up, relapse occurred in 12.1% of the dexamethasone patients and 9.8% of those on prednisone. The trial was designed as a noninferiority trial, and the upper limit of the 95% confidence interval surrounding the difference of 2.3% (−4.1% to 8.6%) was larger than the prespecified criterion for noninferiority, 8%. Therefore, the authors concluded that the single dose of dexamethasone was

not equivalent to the 5-day course of prednisone.


This trial was limited by its very high rate of loss to follow-up. Nevertheless, its results are consistent with prior research, and therefore I conclude that a single dose of 12­mg dexamethasone by mouth seems a reasonable alternative to a 5­-day course of prednisone for adults with acute asthma exacerbations. A larger trial with better follow-up would be worthwhile to confirm this conclusion, since this is such a common condition.

Personal comment: With respect to the reviewer, I am bothered by this approach to the data. The abstract clearly states that a single dose of dexamethasone is NOT equivalent to 5 days of prednisone. And, there was a high loss of data from the original data set of 465 patients. It could very well be that these patients did very well or very poorly and were not interested in follow up. The reviewer then concludes that “nevertheless”, the results are supportive of a single dose of dexamethasone. If the purpose of research is to generate data that will be added to large data collections in the cloud and/or will be included later in a meta­analysis, then this study has validity. But as a standalone study, it fails to support its hypothesis. It’s no fun to invest so much time in a study just to say it failed in its primary purpose. But if ALL research published would also post its original data, this would be a boon to medical research.


Rehrer MW et al. A randomized controlled noninferiority trial of single dose of oral dexamethasone versus 5 days of oral prednisone in acute adult asthma. Ann Emerg Med 2016 Apr 22; [e­pub]. (­0644%2816%2900215­8/abstract)