title: Theophylline as 'add-on' therapy to cetirizine in patients with chronic idiopathic urticaria. A randomized, double-blind, placebo-controlled pilot study.
abstract: BACKGROUND
  Chronic urticaria is a prevalent condition associated with substantial disability. Its pathogenesis is not clearly understood and is divided into autoimmune and chronic idiopathic urticaria (CIU). We investigated if the non-specific phosphodiesterase inhibitor theophylline could provide additional benefit to the histamine-1 receptor (H-1R) antagonist cetirizine in CIU.
  
  
  METHODS
  This was a double-blind, placebo-controlled, parallel study. Patients were randomized to receive either cetirizine and theophylline (200 mg twice daily; group A, 67 subjects) or cetirizine and placebo for 6 months (group B, 67 subjects). Group A patients took theophylline for 6 more months. Response was assessed by visual analog scale (VAS) and treatment effectiveness score (TES). Blood theophylline levels were also determined at visit t=1 and t=7.
  
  
  RESULTS
  The study was completed by 54 of the 67 patients (80.6%) in group A and 51 of the 67 patients (76.1%) in group B. The physician VAS values for group A were lower after t=3, while the patient VAS values were decreased after t=2. The physician and patient TES values in group A were statistically higher (p<0.05) at all time points except for t=1. At least 1 month of theophylline addition was necessary to obtain statistically significant benefit over cetirizine, and reducing theophylline by 50% during phase 2 did not alter this benefit. Pruritus values were reduced, but not statistically significant.
  
  
  CONCLUSIONS
  Addition of theophylline to conventional H-1R antagonists was well tolerated without any adverse effects and provided considerable additional benefit in the management of CIU.
authors.affiliation: Division of Allergy, Attikon Hospital, University of Athens School of Medicine, Athens, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kalogeromitros
authors.forename: Duraisamy
authors.initials: D
authors.lastname: Kempuraj
authors.forename: Alexandra
authors.initials: A
authors.lastname: Katsarou-Katsari
authors.forename: Michael
authors.initials: M
authors.lastname: Makris
authors.forename: Stamatis
authors.initials: S
authors.lastname: Gregoriou
authors.forename: Dean
authors.initials: D
authors.lastname: Papaliodis
authors.forename: Theoharis C
authors.initials: TC
authors.lastname: Theoharides
mesh_terms: D000293:Adolescent; D000328:Adult; D017332:Cetirizine / Q000627:therapeutic use*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D039563:Histamine H1 Antagonists, Non-Sedating / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D010865:Pilot Projects; D013806:Theophylline / Q000627:therapeutic use*; D014581:Urticaria / Q000188:drug therapy*
chemical_list: D039563:Histamine H1 Antagonists, Non-Sedating; D010726:Phosphodiesterase Inhibitors; D013806:Theophylline; D017332:Cetirizine