title: Effect of decursin on the pharmacokinetics of theophylline and its metabolites in rats.
abstract: BACKGROUND
  Decursin is used as a traditional Asian medicine to treat various women's diseases.
  
  
  OBJECTIVE
  Herb-drug interaction has become a serious problem since herbal medicine is extensively used in the modern world. This study investigates effects of decursin, on the pharmacokinetics of theophylline, a typical substrate of cytochrome P450 1A2 enzyme, in rats.
  
  
  METHODS
  After decursin pretreatment for 3 days, on the fourth day rats were administered decursin and theophylline concomitantly. The blood theophylline and its major metabolites (1-methylxanthine (1-MX), 3-methylxanthine (3-MX), 1-methyluric acid (1-MU), and 1,3-dimethyluric acid (1,3-DMU)) levels were monitored with LC-MS/MS.
  
  
  RESULTS
  The results indicated that the clearance, elimination rate constant (K(el)) of theophylline was significantly decreased and area under concentration-time curve (AUC), C(max), half-life was increased in decursin (25mg/kg) pretreatment when theophylline (10mg/kg) was given. In the presence of decursin, the pharmacokinetic parameters of three metabolites (1-MX, 1,3-DMU, and 1-MU) were affected and the differences were statistically significant about AUC(24)(h) parameter.
  
  
  CONCLUSIONS
  Our results suggest that patients who want to use CYP1A2-metabolized drugs such as caffeine and theophylline should be advised of the potential herb-drug interaction, to reduce therapeutic failure or increased toxicity of conventional drug therapy.
authors.affiliation: College of Pharmacy, Chungnam National University, Daejeon, Korea.
authors.forename: Jung-woo
authors.initials: JW
authors.lastname: Chae
authors.forename: In-hwan
authors.initials: IH
authors.lastname: Baek
authors.forename: Kwang-il
authors.initials: KI
authors.lastname: Kwon
mesh_terms: D029969:Angelica; D000818:Animals; D001578:Benzopyrans / Q000494:pharmacology*; D001993:Bronchodilator Agents / Q000097:blood / Q000493:pharmacokinetics*; D002087:Butyrates / Q000494:pharmacology*; D041743:Herb-Drug Interactions; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013806:Theophylline / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D001578:Benzopyrans; D001993:Bronchodilator Agents; D002087:Butyrates; D013806:Theophylline; C101278:decursin