Background

Lactobacillus acidophilus (L. acidophilus) is a type of probiotic ("good" bacteria) found in the human gut, mouth, and vagina, and also in certain foods.

"Good" bacteria such as L. acidophilus can help break down food, absorb nutrients, and fight off "bad" organisms that might cause diseases. L. acidophilus is sometimes added to fermented foods like yogurt and is also found in probiotic supplements.

People commonly use L. acidophilus for diarrhea from antibiotics, as well as irritable bowel syndrome (IBS), overgrowth of bacteria in the vagina, and an infection caused by the bacteria Helicobacter pylori (H. pylori). It is also used for acne, hay fever, eczema, and many other conditions, but there is no good scientific evidence to support many of these other uses. There is also no good evidence to support using L. acidophilus COVID-19.

Don't confuse L. acidophilus with other probiotics, or with fermented food products such as fermented milk, kefir, or yogurt. These are not the same. Also note that the Lactobacillus genus was split up into 25 different genera in April 2020. Some other species' names changed, but L. acidophilus remained the same.

Safety Safety definitions

When taken by mouth: L. acidophilus is likely safe. It's been used safely together with other probiotics for up to 9 months. Some people might experience gas or bloating, but it's usually well-tolerated.

When applied to the vagina: L. acidophilus is likely safe. It's been used safely for up to 12 weeks.

Special Precautions & Warnings:

Pregnancy: L. acidophilus is possibly safe when taken by mouth during pregnancy. It's been used safely together with other probiotics for 6 weeks, starting at 24-28 weeks of pregnancy.

Breast-feeding: There isn't enough reliable information to know if L. acidophilus is safe to use while breast-feeding. But there's no reason to expect safety concerns when used appropriately under medical supervision.

Children: L. acidophilus is likely safe when taken by mouth appropriately in most children. It's been used safely alone and together with other probiotics. However, there isn't enough reliable information to know if L. acidophilus is safe for very small premature infants.

Weakened immune system: Some probiotics have caused blood infections in a small number of people with weakened immune systems. If you have a weakened immune system, talk with your healthcare provider before taking probiotics, including L. acidophilus.

Damaged heart valves: Some probiotics have caused infections of the inner lining of the heart chambers and heart valve. This is extremely rare, but people with damaged heart valves should stop taking probiotics like Lactobacillus acidophilus before dental procedures or surgical procedures.

Effectiveness

Dosing & administration

L. acidophilus is sometimes added to fermented foods such as yogurt, but it's most commonly used in dietary supplements.

In adults, L. acidophilus has most often been taken by mouth, alone or together with other probiotics, in doses of up to 60 billion CFUs daily for up to 6 months. In children, L. acidophilus has most often been taken by mouth in doses of up to 30 billion CFUs daily, for up to 3 months. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Interactions with pharmaceuticals

Antibiotic drugs

Interaction Rating=Moderate Be cautious with this combination.

L. acidophilus is a type of friendly bacteria. Antibiotics are used to reduce harmful bacteria in the body. Taking antibiotics along with L. acidophilus can reduce the effects of L. acidophilus. To avoid this interaction, take L. acidophilus products at least 2 hours before or after antibiotics.

Interactions with herbs & supplements

There are no known interactions with herbs and supplements.

Interactions with foods

There are no known interactions with foods.