title: Absorption pharmacokinetics of clonidine nasal drops in children.
abstract: BACKGROUND
  The alpha2 agonist clonidine has become a popular drug for premedication in children. Effects and pharmacokinetics after oral, rectal, and intravenous administration are well known. The aim of this study was to investigate the absorption pharmacokinetics of clonidine nasal drops in children.
  
  
  METHODS
  Thirteen ASA I pediatric patients received after induction of anesthesia 4 mcg x kg(-1) of clonidine by the nasal route. Blood samples were taken during a 12-h period and plasma levels of clonidine were analyzed by liquid chromatography-mass spectrometry. Data were calculated by a computer-aided curve-fitting program.
  
  
  RESULTS
  Plasma pharmacokinetics following administration of clonidine nasal drops showed a considerable interindividual variability and absorption was delayed and limited. A total of 95% confidence intervals for maximum plasma concentration and time to achieve maximum plasma concentration were 0.4-0.6 ng x ml(-1) and 1.4-3.0 h, respectively.
  
  
  CONCLUSIONS
  Clonidine nasal drops are erratically absorbed from the nasal mucosa and, thus, this mode of drug administration is not recommended for premedication purposes.
authors.affiliation: Department of Anaesthesia and Intensive Care, University Hospital, Policlinico Umberto I, Rome, Italy. n.almenrader@gmail.com
authors.forename: Nicole
authors.initials: N
authors.lastname: Almenrader
authors.forename: Peter
authors.initials: P
authors.lastname: Larsson
authors.forename: Maurizio
authors.initials: M
authors.lastname: Passariello
authors.forename: Roberta
authors.initials: R
authors.lastname: Haiberger
authors.forename: Paolo
authors.initials: P
authors.lastname: Pietropaoli
authors.forename: Per-Arne
authors.initials: PA
authors.lastname: Lönnqvist
authors.forename: Staffan
authors.initials: S
authors.lastname: Eksborg
mesh_terms: D000042:Absorption; D000281:Administration, Intranasal; D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D000768:Anesthesia, General; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D003000:Clonidine / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009297:Nasal Mucosa / Q000378:metabolism; D019999:Pharmaceutical Solutions; D011229:Preanesthetic Medication; D013057:Spectrum Analysis
chemical_list: D000316:Adrenergic alpha-Agonists; D019999:Pharmaceutical Solutions; D003000:Clonidine