Case Study: Antidepressant use in IBS

IBS (Irritable Bowel Syndrome) is a issue I come across in my practice.  A 62 year old female has complaints of diarrhea predominant IBS and is taking the following medications:

  • Aspirin
  • Metoprolol
  • Colestipol
  • Imodium
  • Acetaminophen

She is diagnosed with new onset of depression and very often when choosing an antidepressant, we choose the antidepressant based upon the side effect profile of the medication.  SSRI’s are generally used first line for depression barring a contraindication or compelling indication.

So with our mini-case above, the primary physician started this patient on sertraline (Zoloft) for the depressive symptoms.  Is this the best choice?  That is always difficult to say as we cannot predict the future, but remember that sertraline is very highly serotonergic and has a tendency to cause a significant amount of diarrhea.  Sertraline is probably not the best choice in this patient due to the diagnosis of predominant diarrhea with the IBS.

Paxil (paroxetine) would be a potential alternative if an SSRI is desired for depression.  It rarely causes diarrhea compared to sertraline and may actually be a little more constipating which could definitely be a benefit to a patient with diarrhea issues.  Remember that Paxil can have some drug interactions that we need to look out for as well.

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  1. Nagla

    Thax for your efforts

    • Eric Christianson

      Thanks for checking out the site!

      • Zannat

        Paxil is not a good choice for geriatric patient (per Beers criteria). Do you think its a good idea to recommend paxil for 62 years old female?

  2. Matthew B Zimmerman

    What about a non-pharmacologic method of countering depression first. Let’s have a nonpharmacologic trial first. Then, rather than trial and error prescribing we consider potential drug interactions with paxil, sertraline and other possible antidepressants. Also I would like a prior medical history / diagnosis of patient before choosing antidepressant and I would consider potentially utilizing pharmacogenomic testing to determine proactively or retroactively patients potential response to antidepressant/medication choice.


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Written By Eric Christianson

August 19, 2015

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