title: Theophylline improves esophageal chest pain--a randomized, placebo-controlled study.
abstract: OBJECTIVE
  The treatment of esophageal (noncardiac) chest pain is unsatisfactory and there is no approved therapy. A previous uncontrolled study suggested that theophylline may be useful. Our aims were to investigate the effects of theophylline on esophageal sensorimotor function and chest pain.
  
  
  METHODS
  In a double-blind study, sensory and biomechanical properties of the esophagus were assessed using impedance planimetry in 16 patients with esophageal hypersensitivity, after intravenous theophylline or placebo. In a second, randomized 4-wk crossover study, oral theophylline and placebo were administered to 24 patients with esophageal hypersensitivity. Frequency, intensity, and duration of chest pain episodes were evaluated.
  
  
  RESULTS
  After IV theophylline, chest pain thresholds (P=0.027) and esophageal cross-sectional area (P=0.03) increased and the esophageal wall became more distensible (P=0.04) compared with placebo. After oral theophylline, the number of painful days (P=0.03) and chest pain episodes (P=0.025), pain duration (P=0.002), and its severity (P=0.031) decreased. Overall symptoms improved in 58% on theophylline and 6% on placebo (P<0.02). There was no order effect.
  
  
  CONCLUSIONS
  Theophylline relaxed the esophageal wall, decreased hypersensitivity, and improved chest pain. Theophylline is effective in the treatment of functional chest pain.
authors.affiliation: Department of Internal Medicine, University of Iowa, Carver College of Medicine, Iowa City, Iowa, USA.
authors.forename: Satish S C
authors.initials: SS
authors.lastname: Rao
authors.forename: Ranjit S
authors.initials: RS
authors.lastname: Mudipalli
authors.forename: Jose M
authors.initials: JM
authors.lastname: Remes-Troche
authors.forename: Craig L
authors.initials: CL
authors.lastname: Utech
authors.forename: Bridget
authors.initials: B
authors.lastname: Zimmerman
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D002404:Catheterization; D002637:Chest Pain / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D004311:Double-Blind Method; D017097:Electric Impedance; D004935:Esophageal Diseases / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D012008:Recurrence; D012044:Regression Analysis; D018709:Statistics, Nonparametric; D013806:Theophylline / Q000008:administration & dosage / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D010726:Phosphodiesterase Inhibitors; D013806:Theophylline