Responses were received from 39 of the surveyed program directors (67%). Twenty-three of those responses (59%) indicated that their PICUs currently use aminophylline for status asthmaticus. All positive respondents (100%) indicated that aminophylline use was based on clinical judgment rather than institutional protocol. Twenty of those using aminophylline (87%) stated that the medication was used only when other treatments had failed. Fourteen of the respondents (61%) whose institution used aminophylline identified a therapeutic range for serum aminophylline levels. Six of these respondents (43%) identified a therapeutic serum level of 10 to 20 μg/mL for aminophylline, the generally accepted therapeutic range.4 There was variation in the reporting of both the minimal effective serum level (mean, 10 μg/mL; range, 5-15 μg/mL) and the toxic serum level (mean, 17.9 μg/mL; range, 10-25 μg/mL).