title: The effect of gastric bypass on the pharmacokinetics of serotonin reuptake inhibitors.
abstract: OBJECTIVE
  Morbidly obese patients frequently present with mood and anxiety disorders, which are often treated with serotonin reuptake inhibitors (SRIs). Having observed that patients treated with SRIs frequently relapse after Roux-en-Y gastric bypass surgery, the authors sought to assess whether SRI bioavailability is reduced postoperatively.
  
  
  METHODS
  Twelve gastric bypass candidates treated with an SRI for primary mood or anxiety disorders were studied prospectively. Timed blood samples for SRI plasma levels were drawn for pharmacokinetic studies before surgery and 1, 6, and 12 months afterward. Maximum concentration, time to maximum concentration, and area under the concentration/time curve (AUC) were determined.
  
  
  RESULTS
  In eight of the 12 patients, AUC values 1 month after surgery dropped to an average of 54% (SD=18) of preoperative levels (range=36%-80%); in six of these patients, AUC values returned to baseline levels (or greater) by 6 months. Four patients had an exacerbation of depressive symptoms, which resolved by 12 months in three of them. Three of the four patients had a reduced AUC level at 1 month and either gained weight or failed to lose weight between 6 and 12 months. Normalization of the AUC was associated with improvement in symptom scores.
  
  
  CONCLUSIONS
  Patients taking SRIs in this study were at risk for reduced drug bioavailability 1 month after Roux-en-Y gastric bypass. The authors recommend close psychiatric monitoring after surgery.
authors.affiliation: Department of Surgery, University of Pittsburgh, PA, USA. hamadg@upmc.edu
authors.forename: Giselle G
authors.initials: GG
authors.lastname: Hamad
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Helsel
authors.forename: James M
authors.initials: JM
authors.lastname: Perel
authors.forename: Gina M
authors.initials: GM
authors.lastname: Kozak
authors.forename: Mary C
authors.initials: MC
authors.lastname: McShea
authors.forename: Carolyn
authors.initials: C
authors.lastname: Hughes
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Confer
authors.forename: Dorothy K
authors.initials: DK
authors.lastname: Sit
authors.forename: Carol A
authors.initials: CA
authors.lastname: McCloskey
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Wisner
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000150:complications / Q000188:drug therapy; D001682:Biological Availability; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000150:complications / Q000188:drug therapy; D009767:Obesity, Morbid / Q000523:psychology / Q000601:surgery; D011569:Psychiatric Status Rating Scales; D017367:Selective Serotonin Reuptake Inhibitors / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D017367:Selective Serotonin Reuptake Inhibitors