title: Decreased Escitalopram Concentrations Post-Roux-en-Y Gastric Bypass Surgery.
abstract: BACKGROUND
  There is a high coincidence between obesity and psychiatric disorders including depression. Depressive disorders are commonly treated with antidepressants, including the selective serotonin reuptake inhibitor Lexapro (escitalopram). Although candidates for elective Roux-en-Y gastric bypass (RYGB) surgery may be treated with escitalopram, drug dosing strategies are typically not adjusted postoperatively. Therefore, studies are needed to better characterize escitalopram drug concentrations in a postsurgical setting.
  
  
  METHODS
  Turbulent flow-liquid chromatographic-tandem mass spectrometric methods were used to quantify escitalopram concentrations in serum in study participants approved for RYGB. Blood was collected from study subjects 2 weeks before surgery, and 2 and 6 weeks postoperatively, to assess the impact of RYGB on systemic drug concentrations.
  
  
  RESULTS
  Twelve samples from 4 study participants were collected and analyzed for serum escitalopram concentrations. Two weeks post-RYGB, although there were minimal changes in each participant's body mass index (<5%), drug concentrations were 33% (4%-71%) decreased as compared with presurgical serum concentrations. There were further decreases in drug concentrations 6 weeks postsurgery. All clinical laboratory values were within normal reference intervals.
  
  
  CONCLUSIONS
  RYGB significantly alters the gastrointestinal tract and impacts escitalopram drug concentrations, even shortly after surgery.
authors.affiliation: Departments of *Pathology, †Medicine, ‡Surgery, and §Psychiatry and Behavioral Sciences, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Marzinke
authors.forename: Athena K
authors.initials: AK
authors.lastname: Petrides
authors.forename: Kimberley
authors.initials: K
authors.lastname: Steele
authors.forename: Michael A
authors.initials: MA
authors.lastname: Schweitzer
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Magnuson
authors.forename: Shauna P
authors.initials: SP
authors.lastname: Reinblatt
authors.forename: Janelle W
authors.initials: JW
authors.lastname: Coughlin
authors.forename: William
authors.initials: W
authors.lastname: Clarke
mesh_terms: D000328:Adult; D018687:Antidepressive Agents, Second-Generation / Q000097:blood; D015283:Citalopram / Q000097:blood*; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D011184:Postoperative Period
chemical_list: D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram