Bacillus clausii is a rod-shaped, Gram-positive, motile and spore-forming bacterium that lives in the soil. It is classified as probiotic; microrganisms that maintain a symbiotic relationship with the host organism. It is currently being studied in respiratory infections and some gastrointestinal disorders. Bacillus clausii, has been found to produce antimicrobial substances that are active against gram positive bacteria including Staphylococcus aureus, Enterococcus faecium, and Clostridium difficile.