Can Probiotics Cause Heart Palpitations?

The buzz is still going strong around probiotics, those beneficial bacteria found in your gut, mouth, skin, lungs, colon and vagina. And while you can find them in certain fermented foods, such as yogurt, kimchi and sauerkraut, some people choose to take probiotic supplements for their daily fix.

If you're among them, you may wonder about the potential side effects, including whether probiotics cause heart palpitations. Here's what to know.

Despite what you may have heard, there's no direct link between probiotics and heart palpitations. "There's no data to suggest that probiotics are associated with heart palpitations," says Deena Adimoolam, MD, a board-certified internal medicine physician and endocrinologist.

Probiotics are generally considered safe, according to the Cleveland Clinic. The most common side effects include mild stomach upset, diarrhea, gas and bloating for the first few days after you start taking them.

Rarely, probiotics may trigger an allergic reaction. An allergic reaction raises your levels of histamine, or certain chemicals made by your immune system, per the National Library of Medicine, and this may lead to skin itching, diarrhea and vomiting as well as more serious issues like breathing trouble. Heart palpitations are not a common symptom of an allergic reaction, though.

"It's possible to have an allergy to probiotics, but it's rare," Dr. Adimoolam says.

If you suspect you're having an allergic reaction to probiotics, stop taking them and reach for an over-the-counter antihistamine like Benadryl to ease your symptoms, Dr. Adimoolam suggests. If you have severe symptoms, such as nausea, vomiting or difficulty breathing, get medical help immediately.

You should never ignore symptoms related to your breathing or heart. Always check in with your doctor if you feel tightness in your chest, a racing heart, have trouble breathing or experience other uncomfortable symptoms after taking probiotics or supplements of any kind, recommends Dr. Adimoolam.

Make sure to tell your physician about any medications and supplements you're taking. They'll also want to know what your diet is like. "And they'll listen to your heart and lungs and might consider checking your heart rhythm with an EKG," she adds.