Probiotics may occasionally cause a temporary increase in digestive gas. But, beyond that, they do not present any known risks for most people. In one trial of 140 healthy infants, formula supplemented with long-chain polyunsaturated fatty acids and probiotics appeared as safe as standard formula, and did not have any effect on infant growth by the end of the 7-month trial. 1 However, individuals who are immunosuppressed could conceivably be at risk for developing a dangerous infection with the probiotic organism itself; at least one person taking immunosuppressive medications has died in this manner. 2 In a detailed review of four studies, researchers concluded that the use probiotics did not benefit patients with severe acute pancreatitis. 3 Furthermore, according to one study, the use of probiotics led to an increased risk of mortality in patients with severe acute pancreatitis, and should, therefore, be avoided under these circumstances. 4
Some probiotic supplements also contain prebiotics like FOS to "feed" the good bacteria. FOS appear to be generally safe. However, they can cause bloating, flatulence, and intestinal discomfort, especially when taken at doses of 15 g or higher daily. People with lactose intolerance intolerance may particularly suffer from these side effects.
Especially during a round of antibiotics, probiotic supplements can help the body in innumerable ways. Since antibiotics kill of beneficial bacteria that is innate to the digestive tract, probiotics can help replenish those that are lost. This can, among other functions, help the body with bowel health, candida overgrowth and general smooth maintenance.1
