title: Controlled-release theophylline inhibits early morning airway obstruction and hyperresponsiveness in asthmatic subjects.
abstract: BACKGROUND
  Nocturnal asthma reflects the severity of the disease, and thus its pharmacologic prevention represents one on the main goals of asthma management.
  
  
  METHODS
  To determine whether controlled-release theophylline inhibits the development of airway obstruction and/or airway hyperresponsiveness early in the morning, we examined 18 subjects reporting recurrent nocturnal asthma. In each subject, after five days' treatment with an 8 PM increasing dose of oral controlled-release theophylline, up to 10 +/- 1 mg/kg or placebo the night before the study day, we measured serum theophylline, FEV1 and PC20FEV1 at 6 AM, 2 PM and 10 PM.
  
  
  RESULTS
  At 6 AM, both FEV1 and PC20FEV1 were significantly higher on theophylline than on placebo (3.52 +/- 0.22 versus 3.17 +/- 0.25 L; P < .005 and 2.76 divided by 3.61 versus 1.55 divided by 3.73 mg/mL; P < .05, respectively). At 2 PM and 10 PM FEV1, but not PC20FEV1, was higher on theophylline than on placebo (3.73 +/- 0.21 versus 3.54 +/- 0.25 L; P < .05 and 3.40 +/- 0.22 versus 3.24 +/- 0.24 L; P < .05). Serum theophylline was 12.8 +/- 1.1 micrograms/ml, 8.9 +/- 0.77 and 9.5 +/- 0.85 at 6 AM, 2 PM and 10 PM, respectively.
  
  
  CONCLUSIONS
  We conclude that an evening dose of controlled-release theophyl line inhibits early morning airway obstruction and hyperresponsiveness, and that it may be helpful in the prevention of nocturnal asthma.
authors: Institute of Occupational Medicine, St. Antonio Hospital, University of Padua, Italy.
authors: S
authors: S
authors: Crescioli
authors: A
authors: A
authors: Dal Carobbo
authors: P
authors: P
authors: Maestrelli
authors: P
authors: P
authors: Boschetto
authors: T
authors: T
authors: Santagada
authors: V W
authors: VW
authors: Steinijans
authors: T S
authors: TS
authors: Hurst
authors: G
authors: G
authors: Parise
authors: L M
authors: LM
authors: Fabbri
mesh_terms: D000280:Administration, Inhalation; D000284:Administration, Oral; D000328:Adult; D000402:Airway Obstruction / Q000150:complications / Q000517:prevention & control*; D001249:Asthma / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D002940:Circadian Rhythm; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume; D006261:Headache / Q000139:chemically induced; D006801:Humans; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage / Q000494:pharmacology; D008875:Middle Aged; D009325:Nausea / Q000139:chemically induced; D013806:Theophylline / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D014202:Tremor / Q000139:chemically induced
chemical_list: D003692:Delayed-Action Preparations; D016210:Methacholine Chloride; D013806:Theophylline