They may also cause malabsorption of food components and ingested medications. Antibiotics selectively kill some bacteria causing a disruption of the delicate balance between the good and bad organisms. When good organisms are lost, the protective barrier they create breaks down and the bad organisms are allowed to multiply. As a result, the use of antibiotics increases the susceptibility to certain infections and may lead to a prolonged carrier state. Administration of ampicillin has been implicated in an extended outbreak of Salmo nella infection amongst hospitalized infants.
Antibiotics lead to the development of resistant bacteria in the colon.
These resistant bacteria can seed other tissues like skin, urinary system, and may spread to other patients in the hospital. Farmers working on farms where antibiotics are used for cattle develop increased numbers of resistant bacteria in their colon. In fact, healthy adults living with patients getting antibiotics can develop resistant strains. There is a difference in the gut flora during health and sickness. Metchnikoff, in 1905, introduced the concept of maintaining or restoring the bowel bacteria by introducing live organisms into the gut to stabilize the balance.