Rachelefsky G S, Katz R M, Siegel S C
Ann Allergy. 1978 Apr;40(4):252-7.
In a double-blind, crossover study a sustained release theophylline preparation was found to be effective and safe while controlling the symptoms and improving the measured pulmonary function of 16 chronic childhood asthmatics. Serum theophylline levels between 2.5 and 8.1 microgram/ml were adequate for control of clinical disease.