Gastrointestinal bacteria

Figure 3 Some interactions between gastrointestinal bacteria and the xenobiotic metabolizing enzyme system of the host. Solid lines, host XME system reactions dotted lines, classes of reactions mediated by gastrointestinal bacteria. Specific examples of reaction classes 1-5 are cited in the text. (Modified from Rowland and Tanaka " )...

Because the oral aminoglycosides are poorly absorbed, they are useful to suppressing gastrointestinal bacteria The oral aminoglycosides kanamycin (Kantrex) and neomycin (Mycifradin) are used preoperatively to reduce the number of bacteria normally present in the intestine (bowel prep). A reduction in intestinal bacteria is thought to lessen the possibility of abdominal infection that may occur after surgery on the bowel. 

Gillis JC, Brogden RN Rifaximin. A review of its antibacterial activity, pharmacokinetic properties and therapeutic potential in conditions mediated by gastrointestinal bacteria. Drugs 1995 49 467-484. 

Newburg, D. S. (1997). Do the binding properties of oligosaccharides in milk protect human infants from gastrointestinal bacteria /. Nutr. 127, 980S-984S. 

Adverse reactions to penicillins are rare diarrhoea can occur due to alteration in normal gastrointestinal bacteria. In fact, penicillins are probably the least toxic drugs known. Hypersensitivity reactions to penicillins occur in up to 10% of patients and vary from mild skin rashes to exfoliative dermatitis and Stevens-Johnson syndrome (immune vasculitis with arthritis, nephritis, central nervous system abnormalities and myocarditis) and from bronchoconstriction to life-threatening anaphylactic shock. 

Decarboxylation and reduction to ethanol. This is the pathway of fermentation in yeast, which is exploited to produce alcoholic beverages. Human gastrointestinal bacteria normally produce lactate rather than ethanol, although there have been reports of people with a high intestinal population of yeasts that do produce significant amounts of ethanol after consumption of resistant starch (section 4.2.2.1). 

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