Lacticaseibacillus casei
Lacticaseibacillus casei


Lacticaseibacillus casei (L. casei) is a type of probiotic ("good" bacteria) found in the infant digestive tract. It produces lactic acid in the gut.

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

People use L. casei for diarrhea and respiratory tract infections. It is also used for eczema, constipation, high blood pressure, and many other conditions, but there is no good scientific evidence to support many of these uses. There is also no good evidence to support using L. casei for COVID-19.

Don't confuse L. casei with other probiotics, or with fermented food products such as fermented milk, kefir, or yogurt. These are not the same. Also note that L. casei used to be classified under the Lactobacillus genus. But Lactobacillus was split up into 25 different genera in April 2020. Some product labels might still list this species as Lactobacillus casei rather than its new name, Lacticaseibacillus casei.
When taken by mouth: L. casei is likely safe. It's been used safely alone and together with other probiotics for up to 8 weeks. Some people might experience gas or bloating, but it's usually well-tolerated.

Special Precautions & Warnings:

Pregnancy: L. casei is possibly safe when taken by mouth appropriately 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. casei is safe to use while breast-feeding. But there's no reason to expect safety concerns when used appropriately under medical supervision.

Children: L. casei is likely safe when taken by mouth appropriately in children. It's been used safely for up to 4 months.

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. casei.

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 L. casei before dental procedures or surgical procedures.


NatMed Pro rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
Likely effective Effectiveness definitions
Possibly effective Effectiveness definitions
  • Diarrhea. Taking L. casei by mouth, alone or with other probiotics, seems to help prevent diarrhea in children. But it's not clear if it helps treat diarrhea.
  • Upper airway infection. Taking L. casei by mouth seems to prevent upper airway infections in adults.
Likely ineffective Effectiveness definitions
Possibly ineffective Effectiveness definitions
  • Airway infections caused by exercise. Taking L. casei by mouth doesn't reduce the risk of developing an airway infection from exercise.
There is interest in using L. casei for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.
Insufficient evidence Effectiveness definitions

Dosing & administration

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

In adults, L. casei has most often been taken by mouth, alone or together with other probiotics, in doses of up to 100 billion CFUs daily for up to 3 months. In children, L. casei has most often been taken by mouth in doses of up to 300 million CFUs daily, for up to 4 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. casei is a type of friendly bacteria. Antibiotics are used to reduce harmful bacteria in the body. Taking antibiotics along with L. casei can reduce the effects of L. casei. To avoid this interaction, take L. casei 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. has licensed monographs from TRC Healthcare.
This monograph was last reviewed on 22/02/2023 11:00:00 and last updated on 05/06/2022 07:28:25. Monographs are reviewed and/or updated multiple times per month and at least once per year.
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