Are probiotics an effective treatment against diarrhea?

Our digestive system plays host to a varied colony (called “flora”) of microorganisms that are essential to digestion and the formation of normal stool. This colony’s equilibrium can sometimes be disturbed, however, which causes diarrhea. There are many possible causes for such a disturbance, such as viral or bacterial infections (e.g. gastroenteritis) and taking certain types of medication (especially antibiotics).

Probiotics are living microorganisms that are taken in order to prevent an intestinal flora imbalance or quickly restore balance to a disrupted flora. They are usually available in the form of capsules or as a powder to be swallowed. They can also be found in certain foods such as yogurt.

The studies that have been published to date on the actual effectiveness of probiotics, however, have not been entirely convincing. This is mainly due to the small cohorts involved (only a few dozen volunteers) and the various techniques used when conducting the research. In addition, the results of one recent study conducted on a specific variety of probiotics do not apply to other probiotic varieties.

Two research teams attempted to compare several small-scale studies in order to come to more generalized conclusions. The first team collated the findings of studies conducted among adults and children with acute, infectious diarrhea (caused by a virus or bacterium, for example). The authors concluded that the use of probiotic organisms along with rehydration therapy was a safe and effective treatment for reducing both the duration of the acute diarrhea episode and the stool frequency.

A second team wanted to analyze studies on the efficacy of probiotics in children with persistent diarrhea. The number of studies on the subject was quite limited, however, so they were not able to draw any clear conclusions.

In light of these findings, it appears that taking probiotics could reduce the duration and intensity of a diarrhea episode caused by an infectious illness. For any other type of diarrhea, such as when it is caused by the use of antibiotics, the data is not yet conclusive enough to rule on their efficacy. Before taking probiotics, speak to your pharmacist, who can provide judicious advice!