4 Supplements That Can Ease IBS-C Symptoms

Irritable bowel syndrome with constipation (IBS-C) causes symptoms of abdominal pain, infrequent stools, and bloating. Medical guidelines for treating IBS-C mention only a few types of supplements, but some discussed include soluble fiber, magnesium, peppermint oil, and probiotics.

1. Soluble Fiber Supplements

Soluble fiber is recommended for people with IBS-C. Soluble fiber pulls water into the intestines and turns into a gel. This gel helps with stool consistency, preventing it from becoming either too loose (diarrhea) or too hard (constipation).

Soluble fiber supplements for IBS, often called “bulk-forming fiber laxatives,” include Metamucil (psyllium) and Citrucel (methylcellulose):

• There is some evidence that a psyllium supplement may help manage the diarrhea and pain of IBS-D.
• Methylcellulose is another type of soluble fiber available in supplement form, which is recommended for managing IBS.

2. Magnesium

Magnesium can help relieve constipation by relaxing the muscles of the digestive system and drawing more water into the intestines. The effect is increased intestinal motility and looser stools.

One of the most common adverse effects of magnesium is diarrhea, so supplements might be counterproductive for people who have IBS with diarrhea or IBS with alternating diarrhea and constipation.

Types of magnesium include:

• Magnesium glycinate: Well absorbed in the gut, has less of a laxative effect than other forms, and is also used for anxiety and sleep
• Magnesium citrate: An osmotic laxative that is in liquid form and is used for occasional constipation
• Magnesium sulfate: Also known as Epsom salt, this osmotic laxative is a “salt” that’s dissolved in water, but hasn’t been studied well in IBS
• Magnesium oxide: Another osmotic laxative, it is inexpensive and sometimes used for constipation, but its use in IBS hasn’t been well studied

3. Peppermint Oil

Studies show enteric-coated peppermint oil supplements are helpful for IBS. Peppermint oil affects the smooth muscle in the digestive system. The muscles of the lower esophageal sphincter (LES), stomach, duodenum (first section of the small intestine), and large intestine are relaxed. Peppermint oil also has anti-spasmotic effects on smooth muscle.

Relaxing the gut muscles helps with constipation because stool moves more effectively through the digestive system. Peppermint oil also helps relieve bloating and gas, as well as the pain or discomfort of IBS.

The American College of Gastroenterology guidelines for treating IBS recommend peppermint oil. The authors note that peppermint relaxes the LES and may lead to indigestion or reflux symptoms (such as heartburn). Enteric-coated peppermint oil, which is released in the small or large intestine, helps avoid reflux.

4. Probiotics

Although several probiotics are marketed for people with IBS, the American College of Gastroenterology does not recommend them. Probiotics are beneficial live microbes normally found in the gut.

The reasons are that there are few high-quality studies on probiotics and IBS, and the available studies have conflicting results. Some studies show no change in IBS symptoms or an increase in bloating (which is a possible adverse effect of probiotics).

Probiotics are heavily marketed and are used by the IBS community. IBS is a disorder of gut-brain interaction in which the brain and the gut negatively affect one another. However, it’s also thought that an imbalance in gut bacteria (the microbiome) may be a trigger for IBS.

There’s not enough research to determine which probiotic strain might work for IBS-C. Probiotics are considered safe for most people when used as directed. People with IBS should ask their healthcare providers about probiotic supplements to avoid wasting time and money on ones that are likely to be ineffective.