Optibac probiotics for travelling abroad is a supplement providing 4 well researched strains of live cultures including lactobacillus acidophilus rosell 52 and saccharomyces boulardii which have been tested to ensure survival through the stomach acids and bile salts to reach the intestines alive it is possible that consuming unfamiliar food and drink in foreign environments could disrupt the fragile balance of good and bad bacteria in the gut which may lead to symptoms such as diarrhoea