title: Residual antimalarial concentrations before treatment in patients with malaria from Cambodia: indication of drug pressure.
abstract: BACKGROUND
  The Thai-Cambodian border has been known as the origin of antimalarial drug resistance for the past 30 years. There is a highly diverse market for antimalarials in this area, and improved knowledge of drug pressure would be useful to target interventions aimed at reducing inappropriate drug use.
  
  
  METHODS
  Baseline samples from 125 patients with falciparum malaria recruited for 2 in vivo studies (in Preah Vihear and Pursat provinces) were analyzed for the presence of 14 antimalarials in a single run, by means of a liquid chromatography-tandem mass spectrometry assay.
  
  
  RESULTS
  Half of the patients had residual drug concentrations above the lower limit of calibration for at least 1 antimalarial at admission. Among the drugs detected were the currently used first-line drugs mefloquine (25% and 35% of patients) and piperaquine (15% of patients); the first-line drug against vivax malaria, chloroquine (25% and 41% of patients); and the former first-line drug, quinine (5% and 34% patients).
  
  
  CONCLUSIONS
  The findings demonstrate that there is high drug pressure and that many people still seek treatment in the private and informal sector, where appropriate treatment is not guaranteed. Promotion of comprehensive behavioral change, communication, community-based mobilization, and advocacy are vital to contain the emergence and spread of parasite resistance against new antimalarials.
authors: Swiss Tropical Institute, Basel, Switzerland.
authors: Eva Maria
authors: EM
authors: Hodel
authors: Blaise
authors: B
authors: Genton
authors: Boris
authors: B
authors: Zanolari
authors: Thomas
authors: T
authors: Mercier
authors: Socheat
authors: S
authors: Duong
authors: Hans-Peter
authors: HP
authors: Beck
authors: Piero
authors: P
authors: Olliaro
authors: Laurent Arthur
authors: LA
authors: Decosterd
authors: Frédéric
authors: F
authors: Ariey
mesh_terms: D000293:Adolescent; D000328:Adult; D000962:Antimalarials / Q000097:blood*; D002160:Cambodia; D002648:Child; D002675:Child, Preschool; D002738:Chloroquine / Q000097:blood; D002853:Chromatography, Liquid; D004351:Drug Resistance; D005260:Female; D006801:Humans; D016778:Malaria, Falciparum / Q000175:diagnosis*; D008297:Male; D015767:Mefloquine / Q000097:blood; D008875:Middle Aged; D011803:Quinine / Q000097:blood; D011804:Quinolines / Q000097:blood; D012641:Selection, Genetic; D044967:Serum / Q000737:chemistry*; D053719:Tandem Mass Spectrometry; D055815:Young Adult; D010879:Piperazines
chemical_list: D000962:Antimalarials; D002738:Chloroquine; D015767:Mefloquine; D011803:Quinine; D011804:Quinolines; C034759:piperaquine; D010879:Piperazines