Antibiotics in inflammatory bowel disease: new choices for an old disease.

A variety of medicines have been used for the treatment of inflammatory bowel disease. Antibiotics have demonstrated promise by improving symptoms and by causing disease remission. The mechanism has never been elucidated, but may be related to elimination of a key pathogen, decreasing the number of bacterial secretory products or defective particles, a direct immune-modulating effect, or reducing secondary bacterial invasion. Treatment has focused on Gram-positive, Gram-negative anaerobes and mycobacteria. Broad-spectrum antibiotics has had positive results, but unfortunately their use has been limited because of side effects. Newer broad-spectrum agents such as the fluoroquinolones have achieved desired effects, including disease remission in small studies, but have never undergone large prospective trials. This paper reviews antibiotic treatment in inflammatory bowel disease and discusses the reasons why certain new agents would be ideal to study.