Probiotics are an alternative medicine that is recognized by the the National Institute of Health in the United States. They are commonly used to prevent and treat certain illnesses and support general wellness. Antibiotics kill gut-friendly bacteria as well as the unfriendly bacteria and probiotics are widely used after antibiotics to offset its side effects. A study published in the Pediatric Infectious Disease Journal in April 2010 shows that probiotics reduce the severity of diarrhea and enhance immunity. It also increases the bioavailabity of Vitamin B, calcium, iron, zinc, copper, and among others.