title: Fenproporex and amphetamine pharmacokinetics in oral fluid after controlled oral administration of fenproporex.
abstract: BACKGROUND
  Fenproporex hydrochloride (FEN) is an anorectic drug used in the treatment of obesity, and its major metabolite is amphetamine (AMP), another central nervous system stimulant. The concentration versus time profile of FEN and its metabolite AMP has been described in classic biological matrices such as plasma and urine; however, there are no reports of such data in oral fluid.
  
  
  OBJECTIVE
  The aim of this study is to describe the pharmacokinetics of FEN and AMP in oral fluid after intake of FEN.
  
  
  METHODS
  Twenty-five milligrams of FEN (1 capsule of Desobesi-m) was orally administered to 6 male volunteers, and oral fluid samples were collected with a Quantisal device during 24.00 hours after drug ingestion. These samples were submitted to solid-phase microextraction before analysis by gas chromatography-mass spectrometry in the selected-ion-monitoring mode, using deuterium-labeled AMP as internal standard.
  
  
  RESULTS
  After FEN administration, both analytes could be detected in oral fluid of all volunteers with an initial detection time varying from 0.50 to 1.00 hour. FEN peak concentrations occurred between 1.00 and 1.50 hours after administration and were between 70.7 and 227.5 μg/L. For AMP, peak concentration occurred between 1.50 and 4.00 hours, reaching 33.0-150.9 μg/L.
  
  
  CONCLUSIONS
  The authors observed that oral administration of FEN resulted in significant amounts of FEN and AMP in oral fluid, showing that oral fluid could be a biological matrix suitable for pharmacokinetic studies for both analytes. Using a compartmental approach, FEN data were best fitted by 1-compartment model with first-order input and output, whereas AMP followed a 2-compartment model with first-order input and output.
authors: Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, 2752 Ipiranga Avenue, Azenha 90610-000 Porto Alegre,Rio Grande do Sul, Brazil. eloisacomiran@gmail.com
authors: Eloisa
authors: E
authors: Comiran
authors: Daniele Zago
authors: DZ
authors: Souza
authors: Paula Otero
authors: PO
authors: Boehl
authors: Kristiane de
authors: Kd
authors: Cássia Mariotti
authors: Flavio
authors: F
authors: Pechansky
authors: Paulina do Carmo Arruda Vieira
authors: Pdo C
authors: Duarte
authors: Raquel Brandini
authors: RB
authors: De Boni
authors: Pedro Eduardo
authors: PE
authors: Fröehlich
authors: Renata Pereira
authors: RP
authors: Limberger
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000662:Amphetamines / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001826:Body Fluids / Q000378:metabolism*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage / Q000493:pharmacokinetics; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009055:Mouth / Q000378:metabolism*; D052617:Solid Phase Microextraction / Q000379:methods; D015813:Substance Abuse Detection / Q000523:psychology
chemical_list: D000662:Amphetamines; D000697:Central Nervous System Stimulants; C026013:fenproporex