<unk>  is a semisynthetic broad spectrum antibacterial drug, derived through chemical modification of the natural antibiotic rifamycin by the Italian company Alfa Farmaceutici. It has very low bioavailability due to its poor absorption after oral administration. Because of this local action within the gut and the lack of horizontal transfer of resistant genes, the development of bacterial resistance is rare. Because of this poor absorption, most of the drug taken orally stays in the gastrointestinal tract where the infection takes place. However, due to drug polymorphisms and differences between crystalline and amorphous forms of the compounds, certain generic drug versions are more readily absorbable than the original brand name version. Mechanism of action<unk>  interferes with transcription by binding to the β-subunit of bacterial RNA polymerase. This results in the blockage of the translocation step that normally follows the formation of the first phosphodiester bond, which occurs in the transcription process. This in turn results in a reduction of bacteria populations, including gas-producing bacteria, which may reduce mucosal inflammation, epithelial dysfunction, and visceral hypersensitivity.<unk>  has broad spectrum antibacterial properties against both gram positive and gram negative anaerobic and aerobic bacteria. As a result of bile acid solubility, its antibacterial action is limited mostly to the small intestine and less so the colon. A resetting of the bacteria composition has also been suggested as a possible mechanism of action for relief of IBS symptoms. Additionally,<unk>  may have a direct anti-inflammatory effect on gut mucosa via modulation of the pregnane X receptor. Other mechanisms for its therapeutic properties include inhibition of bacterial translocation across the epithelial lining of the intestine, inhibition of adherence of bacteria to the epithelial cells, and a reduction in the expression of proinflammatory cytokines.
Rifaximin
Ursodeoxycholic acid
Chenodeoxycholic acid
Lactulose
Piretanide
Sucralfate
Cefiderocol
Rifapentine