Study to Examine the Effect of Gastric Bypass Surgery on Venlafaxine ER Blood Levels


About this study

The purpose of the study is to determine whether a significant and predictable change in bioavailability of extended-release venlafaxine occurs following Roux-en-Y gastric bypass.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion criteria:

  • Approved to undergo Roux-en-Y gastric bypass surgery (cost of surgery is NOT included in the study)

Exclusion criteria:

  • Pregnant
  • Allergy to venlafaxine or desvenlafaxine
  • Psychiatric hospitalization within the prior 12 months
  • Active professional treatment for recent substance abuse within 12 months of abstinence
  • Ongoing psychologic issues, such as personality disorders, difficulties as a trauma survivor, or difficulties with depression unless a stable, documented course of treatment by a licensed mental health professional is available
  • Current use of any of the following medications/supplements: 5-hydroxytryptophan, almotriptan, amitriptyline, amoxapine, amoxicillin-clavulanate, amphetamine-dextroamphetamine, atazanavir, bupropion, cinacalcet, citalopram, clarithromycin, clomipramine, desipramine, desvenlafaxine, dextroamphetamine, dextromethorphan, doxepin, duloxetine, eletriptan, entacapone, escitalopram, fluoxetine, fluvoxamine, frovatriptan, haloperidol, imipramine, isocarboxazid, itraconazole, jujube seed extract, linezolid, maprotiline, methylene blue, metoclopramide, metoprolol, milnacipran, mirtazapine, naratriptan, nefazodone, nelfinavir, nortriptyline, paroxetine, phenelzine, procarbazine, protriptyline, quinidine, rasagiline, ritonavir, rizatriptan, saquinavir, selegiline, sertraline, St. John's wort, sumatriptan, tapentadol, terbinafine, toremifene, tramadol, tranylcypromine, trazodone, trifluoperazine, trimipramine, tryptophan, L-tryptophan, venlafaxine, vilazodone, zolmitriptan

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Carrie Krieger, Pharm.D., R.Ph.

Closed for enrollment

More information


Publications are currently not available

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