Oral probiotics are dietary supplements that contain bacteria or other microorganisms that are beneficial to the body, usually the digestive system. They generally contain concentrated amounts of bacteria that are naturally present in the body. As of 2011 most research about probiotics is incomplete, but suggested that they may help prevent or treat certain types of diarrhea, allergies and cancer. For best results, you should choose oral probiotics that contain organisms to help with your specific health concerns.
A priobiotic supplement will be labeled with the genus, species, and strain of bacteria or other organisms it contains. For instance, a probiotic labeled "Lactobacillus casei Shirota" contains the bacteria from the genus Lactobacillus, the species casei and the strain Shirota. Sometimes the genus is abbreviated, as in "L. casei Shirota." Since different strains even of the same species might not have the same effects, you should be sure to choose the exact strain recommended for your condition.
The use of oral probiotics that has the greatest scientific evidence for its effectiveness is treating or preventing diarrhea. Patients often experience diarrhea as a side effect of antibiotics, which may upset the balance of healthy, naturally occurring bacteria in the digestive system. Probiotics can help restore this balance and shorten the duration of a bout of diarrhea caused by antibiotics. The specific type of oral probiotics that have been proved most effective for this is Lactobacillus rhamnosus GG. This strain may also help a patient recover more quickly from traveler's diarrhea.
Oral probiotics may also reduce infants' chances of developing allergies or eczema later in childhood. The incidence of childhood allergies in industrial countries has risen in recent decades, and some researchers believe it is partially due to the increased consumption of processed food that lacks healthy bacteria. Especially in infants who are bottle-fed, the probiotic Lactobacillus rhamnosus GG may help compensate for this lack. You should, however, consult with a pediatrician before giving oral probiotics to infants.
The bacteria Lactobacillus casei Shirota and Bifidobacterium lactis Bb12 are sometimes used as a preventative for colon cancer. These strains of bacteria are thought to aid in removing carcinogens — cancer-causing chemicals — from the digestive system. Patients who had cancerous polyps removed from their colons were less likely to develop more polyps if they took a regular dosage of one of these two probiotics.
Since they contain bacteria that is already present in the body, probiotics are generally considered a very safe alternative treatment for these and some other conditions when taken in the recommended amounts. People who have compromised immune systems, however, may be at risk for developing infections from probiotic supplements. You should consult a doctor before starting oral probiotics if you have any condition that may weaken your immune system.