title: The neurobehavioural effects of kava.
abstract: OBJECTIVE
  This review considers the context in which kava is used, together with its underlying psychopharmacological mechanisms, to investigate the neurobehavioural effects associated with kava use.
  
  
  METHODS
  We conducted a systematic search using the computerized databases MEDLINE, OVID and PsychLIT for all articles containing any of the following words: kava, kavain, kawa and Piper methysticum. In the opinion of the authors, all articles from this collection containing data that could inform the neurological and cognitive sequelae of kava use were included for the purpose of this review.
  
  
  RESULTS
  The use of kava occurs among indigenous populations in the South Pacific and in northern Australia, while also being used throughout the western world as a herbal medicine. Animal studies show that kava lactones alter neuronal excitation through direct interactions with voltage-dependent ion channels, giving rise to kava's muscle relaxant, anaesthetic, anxiolytic and anticonvulsive properties. Several isolated cases of psychotic and severe dystonic reactions following kava use suggest that kava also has psychoactive properties, yet there is no conclusive evidence that kava interferes with normal cognitive processes.
  
  
  CONCLUSIONS
  Kava is effective in the treatment of tension and anxiety. There may be risk-factors for severe motor and psychiatric responses to kava use, although these are not well-understood. Given the increasingly widespread use of kava, further investigation is necessary to gain an understanding of its immediate neuropsychiatric effects and long-term cognitive effects.
authors.affiliation: Mental Health Research Institute, Melbourne, Australia 3052. sheree@neuro.mhri.edu.au
authors.forename: Sheree
authors.initials: S
authors.lastname: Cairney
authors.forename: Paul
authors.initials: P
authors.lastname: Maruff
authors.forename: Alan R
authors.initials: AR
authors.lastname: Clough
mesh_terms: D000328:Adult; D001264:Athetosis / Q000139:chemically induced*; D002819:Chorea / Q000139:chemically induced*; D002986:Clinical Trials as Topic; D003071:Cognition / Q000187:drug effects*; D004311:Double-Blind Method; D006801:Humans; D020901:Kava / Q000009:adverse effects*; D008297:Male; D011605:Psychoses, Substance-Induced / Q000209:etiology*