Do Antibiotics Weaken Your Immune System? + 3 Ways To Help

Experiencing a pandemic has a way of making people reassess their overall health and lifestyle habits. While getting adequate sleep and eating a nutrient-dense diet may seem obvious, other seemingly standard practices—like taking antibiotics—might not be as beneficial.

Unnecessary use of antibiotics, as well as over-the-counter drugs, may disrupt gut health. "Though in the right context, these drugs can be good for our health," internal medicine doctor Austin Perlmutter, M.D., previously told mbg, "over time, and when used inappropriately, they appear to disrupt the health of the microbiome and gut barrier." 

In fact, integrative physician Vincent Pedre, M.D., says, "Overprescribed antibiotics are the No. 1 reason for gut dysbiosis," or an imbalance of gut bacteria. This is because while antibiotics (also called antibacterials) do their job of killing or slowing the growth of bad bacteria, they may also mess with the good kind. 

"In fact, antibiotic-induced microbiota alterations1 can remain after long periods of time, spanning months and even years," one study says. This change in the gut microbiome may end up affecting immunity. 

According to functional medicine doctor Wendie Trubow, M.D., 70 to 80% of our immune system is actually found in the gut. This means that the gut and the immune system are in constant communication. 

"Anything that alters the normal state of the gut and its flora can impact its function," she says, "and antibiotics kill off a wide swath of the microbiome."  

Taking a probiotic can enhance gut health and aid in replenishing the good bacteria in your microbiome. Trubow recommends taking a broad-strain probiotic for at least six months after a course of antibiotics. (Learn how to find the right probiotic for you here.)

After finishing a course of antibiotics, functional medicine doctor Amy Shah, M.D., also recommends eating a healthy prebiotic- and probiotic-rich diet.

Prebiotics help nourish probiotics, and they are found in foods like asparagus, jicama, garlic, and leeks. Probiotics are commonly found in fermented foods, like yogurt, kefir, kimchi, and pickles. "Take it slow in the beginning, as it may be hard to digest some of these things," Shah adds.

Processed carbohydrates and sugars can take a negative toll on gut health. "Studies show animals fed a high-fat, high-sugar diet—very similar to what you'll find in many processed foods—have a less diverse and less healthy range of gut flora2," Pedre writes for mbg. Swapping processed desserts or chips with healthy snacks, fruits, and vegetables may enhance gut health. 

Studies have shown that exercise can alter the gut microbiome3 and support overall health. Moderate exercise can also help reduce stress, which can have an impact on the gut microbiome via the gut-brain axis4. Adding yoga, Pilates, or a brisk walk to a daily routine may help restore a balanced gut microbiome. 

If a doctor prescribes antibiotics, it's probably for a good reason. "Antibiotics are important for bacterial infections," Trubow says, like urinary tract infections (UTI), bacterial pneumonia, strep throat, mastitis, and more. These infections will generally respond to antibiotics in about a week, she says, and alterations to the gut will occur after just a few doses. At that point, she says, it's better to complete the course and make sure the infection is gone—then you can work on healing the gut.