Figure 1.

A summary of selected mechanisms by which the microbiota influences drug pharmacokinetics. Individual panels correspond to the article text. 1.1 Agents including lovastatin or sulfasalazine are directly activated by the gut microbiota. 1.2 The availability and uptake of drugs including simvastatin and amiodarone is influenced by the microbiota or by co-administration of probiotics through unknown mechanisms. 1.3 Toxicity of irinotecan is elevated by microbial β-glucuronidase activity and can be selectively inhibited by antibiotics or specific microbial β-glucuronidase inhibitors. 1.4 Digoxin is inactivated in the gut by specific enzymatic activity associated with specific strains of Eggerthella lenta (cgr+). 1.5 Paracetamol detoxification in the liver is competitively inhibited by the gut microbial metabolite p-Cresol.