Can Probiotics Cause Gas? Doctors Explain The Unexpected Side Effect

We get it...it stinks. So, to help make sense of this potential, unexpected side effect, mbg dug into the research and chatted with functional medicine doctors. Here's what they have to say. (Curious about other potential side effects of probiotics? Check out our guide.)

The short answer is: sometimes. One study on probiotics states that flatulence and bloating are, in fact, two of the most common side effects1. Yet, "probiotics are generally considered safe and well tolerated," the authors note.* 

According to integrative medicine doctor Bindiya Gandhi, M.D., "Everyone's microbiome is always changing." If you're suddenly introducing a new bacteria to the environment—even if it's a good bacteria—the microbiome will have to adjust. "This usually happens when someone has a gut imbalance of good and bad bacteria," Gandhi adds. 

If the side effects don't subside after a few weeks of taking probiotics, visit a doctor or gastroenterologist. "Definitely talk to your functional or integrative doctor because that is a telltale sign something else is going on underneath," Gandhi says. In the meantime, you may need to stop taking the probiotic you're currently on and find one with targeted strains that meet your specific digestive needs.* 

Probiotic supplements contain living bacteria, which are meant to help balance the gut microbiome.* However, the introduction of new bacteria might temporarily unsettle your gut microbiome, leading to side effects like gas. After a few weeks, however, probiotics have been shown to support various aspects of digestive health.* If the symptoms haven't gone away by then, check in with your doctor.