Video: Antidepressants for IBS?
Antidepressants are neuromodulators that have the ability to impact nerve signaling. This nerve signaling is regulated by chemicals called neurotransmitters. These chemicals are released from nerves and bind to other nerves, muscles, and glands. The result impacts pain signaling and can potentially increase or decrease GI function. These drugs often affect GI symptoms at lower dosages than used to treat depression or anxiety.
Types of Antidepressants/Neuromodulators
Multiple classes of neuromodulators exist. The ones most commonly used to treat IBS symptoms include the tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs). There is some agreement across international guidelines that TCAs are effective for treating IBS; however, recommendations for using SSRIs remain conflicted.
TCA’s that are commonly used include amitriptyline (Elavil®), nortriptyline (Pamelor®), imipramine (Tofranil®) and desipramine (Norpramin®). The choice in many instances is based on healthcare provider preference and possible side effects. The most commonly seen side effects include drowsiness and dry mouth. Dry eyes, blurred vision, urinary retention and constipation may also occur.
The most well studied SSRI drugs include citalopram (Celexa®), fluoxetine (Prozac®) and Paroxetine (Paxil®). Some healthcare providers also like to use sertraline (Zoloft®) given its anti-anxiety properties. Unlike the TCAs, these drugs are often used in doses similar to those used to treat anxiety and depression (10-40mg/day). Risk of side effects from SSRI drugs are often milder than TCAs. Common side effects include drowsiness, dry mouth, diarrhea, headaches, blurred vision, and/or reduced sexual desire.
Be aware that the effectiveness of various agents differs between individuals and a medication regimen must be carefully chosen by the patient and their healthcare provider.
Last modified on May 18, 2021
Adapted from IFFGD Publication #168 “Current Pharmacologic Treatments for Adults with Irritable Bowel Syndrome” By: Darren M. Brenner, MD, Associate Professor of Medicine and Surgery, Northwestern University – Feinberg School of Medicine, Chicago, Illinois; Adapted from an article by: Tony Lembo, MD, Professor, of Medicine and Rebecca Rink MS, Beth Israel Deaconess Medical Center, Harvard Medical School, MA; Edited by: Lin Chang, M.D., Professor of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA