Rifaximi (Xifaxan)

Description

Rifaximin is a poorly absorbed, broad-spectrum antibiotic that belongs to the rifamycin class of antimicrobial agents. In colorectal cancer care, rifaximin is used as supportive therapy to manage treatment-related bowel complications, specifically post-surgical bowel dysfunction following anterior resection for rectal cancer and radiation-induced diarrhea during radiotherapy. This antibiotic works locally in the gastrointestinal tract to reduce bacterial overgrowth and inflammation that can contribute to these debilitating side effects. Rifaximin helps maintain quality of life during cancer treatment by addressing gastrointestinal complications rather than treating the cancer itself.

Mechanism of Action

Rifaximin binds to the beta-subunit of bacterial DNA-dependent RNA polymerase, blocking bacterial RNA synthesis and inhibiting bacterial protein production. Due to its minimal systemic absorption (less than 0.4%), the drug acts primarily within the intestinal lumen to alter gut microbiota composition and reduce bacterial translocation and endotoxin production that contribute to inflammation and diarrhea.

Molecular Targets

Side Effects

Not all side effects are listed. Side effects vary by individual. Always consult your oncologist.

Clinical Trials