Peppermint Oil Capsules for IBS: What the Trials Show
Bloating & DigestionArticleEnteric-coated peppermint oil is one of the few store-bought IBS remedies with guideline support. The benefit is modest, heartburn is the usual trade-off, and the label matters.
In this article
Peppermint oil capsules sit on the digestive aisle next to probiotics and fiber, marketed for cramping, bloating and irritable bowel syndrome (IBS). Unlike many gut supplements, they have a body of clinical trials behind them. Here is what the trials found and what to check before you buy.
What the evidence says
The National Center for Complementary and Integrative Health (NCCIH)1 says a small amount of research suggests enteric-coated peppermint oil capsules may improve IBS symptoms in adults.1
- Pooled trials. A 2022 review of 10 studies with 1,030 people found peppermint oil beat placebo for overall IBS symptoms and belly pain. It also caused more side effects, mostly mild acid reflux and indigestion.1
- Guideline. A 2021 American College of Gastroenterology2 guideline recommended peppermint oil for relief of overall IBS symptoms.1
- A larger, stricter trial. In a 2020 Dutch trial, 190 people with IBS took peppermint oil or placebo for 8 weeks. On the main goal, a strict measure of pain response, peppermint oil didn’t do significantly better: 46.8% responded compared with 34.4% on placebo. The version released in the small intestine did improve pain, discomfort and overall IBS severity on secondary measures. Mild side effects were more common with peppermint oil.2
The takeaway: for some people peppermint oil eases IBS pain modestly. It isn’t a cure, and it won’t help everyone.
It’s for IBS, not general indigestion
NCCIH notes that peppermint oil on its own may worsen indigestion in some people.1 If your main problem is heartburn or an upset stomach after meals, see our guides to heartburn and GERD and the heartburn aisle.
Before you buy
- Look for “enteric-coated.” Capsules are often coated so they release past the stomach, to reduce the chance of heartburn.1
- Swallow capsules whole. Chewing or opening them defeats the coating.
- Expect possible side effects. NCCIH lists heartburn, nausea, belly pain and dry mouth, and rarely allergic reactions.1
- Give it a defined trial. The 2020 trial lasted 8 weeks.2 Track your symptoms before and during, and stop if it isn’t helping.
- Tell your clinician and pharmacist, especially if you take other medicines or have reflux.
Make sure it’s IBS first
New bowel symptoms after 50 deserve a checkup before you self-treat. NIDDK lists symptoms that may point to a problem other than IBS: anemia, bleeding from the rectum, bloody or black, tarry stools, and weight loss.3 Your doctor will also ask about a family history of digestive diseases such as celiac disease or colon cancer.3 Our guide to IBS symptoms and diagnosis explains the process.
Try: “I’ve had cramping and changing bowel habits for months. Before I try peppermint oil, can we make sure this is IBS, and is it safe with my reflux and other medicines?”
Bloated by Dinner includes a Belly Clock log and a Test-It list with a visit script. Use them to record your symptoms before and during an 8-week trial, so you and your clinician can judge whether it’s helping. See the book.
This article is for general educational purposes only and is not medical advice. It isn't a substitute for diagnosis or treatment from a qualified healthcare professional who knows your health history. Please don't ignore professional advice or delay getting care because of something you read here. If you think you may be having a medical emergency, call 911 or your local emergency number right away. This article discusses a category of supplement and published research. It does not evaluate any particular brand or product. Girl Playbook does not endorse any specific product, test, or provider.
Girl Playbook sells this book. It provides education and worksheets, not individualized medical care.
Sources
The research behind this article, in the order it’s cited. How we source our articles.
- National Center for Complementary and Integrative HealthPeppermint Oil (opens in a new tab)abcdefg
- Gastroenterology (abstract via PubMed), 2020Efficacy and Safety of Peppermint Oil in a Randomized, Double-Blind Trial of Patients With Irritable Bowel Syndrome (opens in a new tab)abc
- National Institute of Diabetes and Digestive and Kidney DiseasesDiagnosis of Irritable Bowel Syndrome (opens in a new tab)ab
Spotted something out of date? Tell us and we’ll check it.
