title: The effect of acute tryptophan depletion on mood and impulsivity in polydrug ecstasy users.
abstract: BACKGROUND
  Several studies suggest users of 3,4-methylenedioxymethamphetamine (ecstasy) have low levels of serotonin. Low serotonin may make them susceptible to lowered mood.
  
  
  OBJECTIVE
  This work aims to study the acute effects on mood and impulsivity of lowering serotonin levels with acute tryptophan depletion in polydrug ecstasy users and to determine whether effects were different in men and women.
  
  
  METHODS
  In a double-blind cross-over study, participants who had used ecstasy at least 25 times (n = 13) and nonuser controls (n = 17) received a tryptophan-deficient amino acid mixture and a control amino acid mixture containing tryptophan, at least 1 week apart. Mood was measured using the profile of mood states, and impulsivity was measured with the Go/No-Go task.
  
  
  RESULTS
  The main result shows that a lowering of mood after acute tryptophan depletion occurred only in female polydrug ecstasy users (n = 7), relative to controls (n = 9). Results from the Go/No-Go task suggested that impulsivity was not increased by acute tryptophan depletion in polydrug ecstasy users.
  
  
  CONCLUSIONS
  The group sizes were small, when males and females were considered separately.
  
  
  CONCLUSIONS
  Women polydrug ecstasy users appear to be more susceptible than men to the effects of lowered serotonin levels. If use of ecstasy alone or in conjunction with other drugs causes progressive damage of serotonin neurons, women polydrug ecstasy users may become susceptible to clinical depression.
authors.affiliation: Department of Psychiatry, McGill University, 1033 Pine Avenue West, Montréal, Québec, H3A 1A1, Canada, simon.young@mcgill.ca.
authors.forename: Simon N
authors.initials: SN
authors.lastname: Young
authors.forename: Martine
authors.initials: M
authors.lastname: Regoli
authors.forename: Marco
authors.initials: M
authors.lastname: Leyton
authors.forename: Robert O
authors.initials: RO
authors.lastname: Pihl
authors.forename: Chawki
authors.initials: C
authors.lastname: Benkelfat
mesh_terms: D000339:Affect / Q000187:drug effects* / Q000502:physiology*; D019969:Amphetamine-Related Disorders / Q000097:blood / Q000378:metabolism* / Q000523:psychology; D000704:Analysis of Variance; D018592:Cross-Over Studies; D004032:Diet; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000097:blood / Q000378:metabolism; D008297:Male; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000494:pharmacology*; D009483:Neuropsychological Tests; D018490:Serotonin Agents / Q000494:pharmacology*; D012737:Sex Factors; D013997:Time Factors; D014364:Tryptophan / Q000097:blood / Q000172:deficiency*; D055815:Young Adult
chemical_list: D018490:Serotonin Agents; D014364:Tryptophan; D018817:N-Methyl-3,4-methylenedioxyamphetamine