Letter: Use of theophylline in asthma.
D000284:Administration, Oral; D000328:Adult; D000367:Age Factors; D001249:Asthma / Q000188:drug therapy*; D002648:Child; D006801:Humans; D013806:Theophylline / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors
D013806:Theophylline