A study on mice found that antibiotics caused changes in microbes in the gastrointestinal (GI) tract that can affect how the immune system responds to common allergens in the lungs, paving the way for allergies and asthma. According to one of the researchers, "Antibiotics knock out bacteria in the gut, allowing fungi to take over temporarily until the bacteria grow back after the antibiotics are stopped. Our research indicates that altering intestinal microflora this way can lead to changes in the entire immune system, which may produce symptoms elsewhere in the body." They believe the findings could help explain why cases of chronic inflammatory diseases, like asthma and allergies, have been increasing rapidly over the last 40 years--a time period that corresponds with widespread use of antibiotics. This is definitely something to keep in mind the next time you consider taking an antibiotic or giving one to your children. There are certainly times when they are necessary but antibiotics are typically widely overused.
Science Blog May 26, 2004