C18 Flashcards
1
Q
MISCELLANEOUS ANTIMICROBIAL
AGENTS?
A
Metronidazole
Fidaxomicin
Rifaximin
2
Q
Metronidazole MOA?
A
- undergoes a reductive bioactivation of their nitro group by ferredoxin (present in anaerobic parasites) to form reactive cytotoxic products that interfere with nucleic acid synthesis
3
Q
Metronidazole PharmacoKinetix?
A
- bioavailability: effective orally
- Distribution: to most tissues (also CNS)
- can also be given intravenously
- available in topical formulations
- Elimination: hepatic metabolism
- dosage reduction may be needed in patients with liver dysfunction
4
Q
MEtronidazole Clinical use?
A
AntiBacterial:
- greatest activity against Bacteroides and Clostridium
- against pseudomembranous colitis
- effective in anaerobic or mixed intra-abdominal infections and in brain abscess
- used in the regimens for the eradication of Helicobacter pylori in gastric ulcers
AntiProtozoal:
- trichomoniasis
- giardiasis
- intestinal amebiasis
- amebic hepatic abscess
5
Q
Metronidazole toxicity?
A
- gastrointestinal irritation
- headache
- leukopenia
- Opportunistic fungal infections may occur during treatment
- Drug interactions: potentiation of coumarin anticoagulant effects
6
Q
Fidaxomicinn MOA?
A
- narrow-spectrum
- antibiotic that is active against G+ aerobes and anaerobes
- inhibits bacterial RNA polymerase
7
Q
Fidaxomycin Clinical uses and toxicity?
A
- used for C difficile infection in adults
- Toxicity is negligible due to limited absorptio
8
Q
Rifaximin MOA?
A
- derivative of rifampin
- it is active against G+ and G- aerobes and anaerobes
- inhibits DNA-dependent RNA polymerase
9
Q
Rifaximin Clinical use?
A
- management of hepatic encephalopathy
- irritable bowel syndrome with diarrhea
- adjunct in cases of refractory C difficile infection in adults
10
Q
Rifaximin Toxicity?
A
negligible due to limited absorption