These Medications Mess with Your Gut Biomes

Janet Tiberian Author
By Janet Tiberian, MA, MPH, CHES
July 13, 2023
Pills spilling out of a tipped bottle

Gut health is a relatively new line of research. As more and more studies are published, experts realize that gut microbiota function like an organ. And like other organs, it’s affected by what you ingest. While you’re probably aware your diet can affect biomes, you may not have thought about medications.

“Medications can be an important component in managing and treating health conditions,” says Bernard Kaminetsky, MD, medical director, MDVIP. “However, they can have side effects, including taking a toll on gut bacteria.”

Antibiotics are perhaps the most notorious medication for disrupting healthy gut bacteria, but they’re not the only ones that can cause havoc. Here’s what you need to know about a few common drugs that may influence your gut flora. 

Antibiotics are very misunderstood. If you have a urinary tract infection, bacterial pneumonia or strep throat, they’re not only necessary, they can be lifesaving. But every time you take round of antibiotics, good and bad strains of bacteria are killed, which can lead to yeast infections and gastrointestinal distress. And taking them too often or unnecessarily raises the risk for leaky gut syndrome, Clostridium difficile colitis (often called a C. diff infection) and antibiotic resistance. This is why it’s not a good idea to take antibiotics for viral infections like colds, flu and some coughs, unless a secondary bacterial infection has developed.

Best Defense: Take a probiotic supplement along with the antibiotic and add fermented, high fiber and prebiotic foods to your diet. Skip grapefruit juice and calcium fortified products while you’re on an antibiotic because they can block its absorption, possibly causing you to need another cycle.  

Antipsychotics help patients with bipolar disorder control mania, depression, delusions and hallucinations. Because there are different classes of antipsychotics, they tend to be a mixed bag in terms of side effects, effectiveness and overall safety. And some subclasses seem to slow the growth of gut bacteria, affecting overall gut biome diversity, according to a study published in Nature. For example, psychotropics (a drug class that includes anti-psychotics, antidepressants, anxiolytics, antiepileptics and mood stabilizers) have an antibacterial effect that can lower the microbiome diversity among patients with depression and anxiety, finds a study published in the International Journal of Neuropsychopharmacology.

Best Defense: Recent studies suggest that a probiotic supplement and foods high in probiotics and prebiotics such as fruits, vegetables, whole grains, nuts and legumes might help. Just talk to your doctor first. 

“There are a few studies suggesting probiotics might help control certain mental illnesses. This fairly new concept is called psychobiotics and it combines using probiotics and prebiotics. If your doctor thinks taking a probiotic supplement might be helpful, try it. It might help balance your gut biomes and control your condition,” says Kaminetsky.

Calcium Channel Blockers
Calcium channel blockers are commonly used to treat high blood pressure, irregular heartbeats, chest pain and coronary artery disease. But like some antipsychotic medications, seems to inhibit microbiota growth.

Best Defense: Try eating a diet high in fruits, vegetables, whole grains, nuts and legumes. Information isn’t available on the effects probiotic supplement can have on taking calcium channel blockers, so if you are interested in trying a supplement, discuss it with your doctor. 

Proton Pump Inhibitors  
Protein pump inhibitor (PPI) is the clinical term for acid reducers and are used to treat ulcers and gastroesophageal reflux disease (GERD). They’re found in the over-the-counter section of most grocery stores and pharmacies and have generic names that end in “zole.” Generally, they’re safe and effective. However, they work by lowering gastric acid secretions, which can decrease microbiome diversity. When used regularly, these drugs can can a bacterial imbalance, according to an article published in the World Journal of Gastroenterology. Too much gut bacteria is associated with SIBO (small intestine bacterial overgrowth), a condition which interferes with healthy digestion. 

Best Defense: If your doctor instructed you to take PPIs on a regular basis, add fermented foods to your diet to help balance your gut bacteria and ease heartburn and GERD. If you’re self-medicating to relieve heartburn and GERD, fermented foods can help, as well as cutting back on coffee, tea, dairy products and citrus fruits. A probiotic supplement can interfere with the effectiveness of a PPI, so check with your doctor before taking one.

It’s important to talk to your MDVIP-affiliated doctor before taking any supplement or making dietary changes. Looking for a primary care physician? Find an MDVIP affiliate near you and begin your partnership in health »

Similar Posts
Keep Your Brain Fit By Keeping Your Gut Healthy / Louis B Malinow, M.D. / March 22, 2016
Simple Steps to Improve Your Gut Health / Louis B Malinow, M.D. / July 11, 2000

About the Author
Janet Tiberian Author
Janet Tiberian, MA, MPH, CHES

Janet Tiberian is MDVIP's health educator. She has more than 25 years experience in chronic disease prevention and therapeutic exercise.

View All Posts By Janet Tiberian, MA, MPH, CHES
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