Can an Antihistamine a Day Keep IBS Pain Away?
At first it sounds implausible, but popping an over-the-counter antihistamine may help relieve some of the symptoms of irritable bowel syndrome (IBS), including stomach pain and bloating, according to a growing body of evidence.
What Are Antihistamines?
The Antihistamine-IBS Connection
“Damage to the gut that occurs with IBS will often travel with sensitivity to histamines, and we know that histamines exist in larger quantities in people with IBS, resulting in inflammation that may worsen IBS symptoms,” explains William J. Bulsiewicz, MD, a gastroenterologist and the author of the book Fiber Fueled.
This drug is not available in the United States. But there are many over-the-counter antihistamines available that work in a similar fashion. These include diphenhydramine (Benadryl), loratadine (Claritin), and cetirizine (Zyrtec). “Some people with IBS may find a benefit from using an antihistamine because it is helping to block the pain signal,” Bulsiewicz says.
- Dry mouth
- Drowsiness
- Excitability
- Vision changes
- Decreased appetite
Note that antihistamines are not formally approved for treatment of IBS, even though there is preliminary evidence that they may play a role in treatment of IBS symptoms. If you are interested in trying antihistamines for IBS relief, talk with your doctor first to make sure it’s the best choice for you.
Other Ways to Treat IBS Symptoms
Managing IBS often involves restoring the balance between good and bad bacteria in the gut. This starts with slowly adding more fiber to your diet. Fiber is a prebiotic, which means it feeds the good bacteria in the gut, helping to restore this balance, Bulsiewicz says.
Foods that contain higher amounts of FODMAPs are fruits such as:
- Apples
- Vegetables (artichokes, asparagus, beans, and cabbage)
- Dairy products
- Foods with high-fructose corn syrup
- Wheat- and rye-based foods
Ask your doctor if this type of diet is worth trying for your symptoms. He or she may suggest a trial that starts with avoiding foods that are high in FODMAPs and then slowly adding them back one by one to determine which, if any, trigger your symptoms.
The Takeaway
- Antihistamines, commonly used for allergies, may also help relieve symptoms of IBS like stomach pain and bloating.
- Potential side effects of antihistamines include dry mouth, drowsiness, and vision changes — talk to your doctor before starting any new medications.
- Increasing dietary fiber is an important strategy for managing IBS symptoms effectively.
- Trying a low-FODMAP diet under medical supervision might also help some individuals with IBS identify specific dietary triggers.
- IBS Facts and Statistics. International Foundation for Gastrointestinal Disorders.
- Irritable Bowel Syndrome. Mayo Clinic. October 11, 2024.
- Irritable Bowl Syndrome (IBS) and Disorders of Gut-Brain Interaction. University of Michigan Health.
- Antihistamines for Allergies. United States National Library of Medicine. May 20, 2024.
- Wouters MM et al. Histamine Receptor H1-Mediated Sensitization of TRPV1 Mediates Visceral Hypersensitivity and Symptoms in Patients With Irritable Bowel Syndrome. Gastroenterology. April 2016.
- Decraecker L et al. Treatment of Non-Constipated Irritable Bowel Syndrome With the Histamine 1 Receptor Antagonist Ebastine: A Randomized, Double-Blind Placebo-Controlled Trial. Gut. February 23, 2024.
- Dietary Guidelines for Americans 2020-2025. United States Department of Agriculture. December 2020.
- Christian B. So, You Want to Increase Your Fiber Intake? University of Massachusetts Chan Medical School. March 14, 2022.
- FODMAP Diet: What You Need to Know. Johns Hopkins Medicine.
Waseem Ahmed, MD
Medical Reviewer
Waseem Ahmed, MD, is an assistant professor of medicine in the Karsh Division of Gastroenterology and Hepatology at Cedars-Sinai Medical Center in Los Angeles and serves as Directo...
