<s>[INST] context: METRONIDAZOLE: It is the prototype nitroimidazole introduced in 1959 for trichomoniasis and later found to be a highly active amoebicide. It has broad-spectrum cidal activity against protozoa, including Giardia Iamblia in addition to the above two. Many anaerobic bacteria, such as Bact. fragilis, Fusobacterium, Clostridium perfringens, Cl. difficile, Helicobacter pylori, Campylobacter, peptococci, spirochetes and anaerobic Streptococci are sensitive. Though, it does not directly inhibit the helminth Dracunculus medinensis, extraction of the worm from under the skin is facilitated. Metronidazole does not affect aerobic bacteria Uses: 1 . Amoebiasis: Metronidazole is a first line drug for all forms of amoebic infection. Many dosage Antiamoebic Drugs 799 regimens have been tried; the current recommendations are: For invasive dysentery and liver abscess-800 mg TDS (children 30- 50 mg/kg/day) for 7- 10 days. In serious cases of liver abscess 1 g may be infused i.v. slowly followed by 0.5 g every 8-12 hr till oral therapy is instituted. For mild intestinal diseas [/INST] question: Which of the following antibiotic is used in the treatment of Clostridium difficile associated diarrhea? | options: A: Ciprofloxacin B: Metronidazole C: Piperacillin D: Clindamycin | answer: B </s>