8.5 Flashcards
What is the MOA of Clindamycin?
Reversible binding of 50S subunit
What is a good alternative to a person who does not respond to co-trimoxazol for PCP
Clindamycin + Primaquine
What is the most important adverse effect of Clindamycin?
Potentially fatal pseudomembranous colitis (C.Diff)
What is Clindamycin mostly used for?
mainly Gram + anaerobes including bacteroides
How does Clindamycin gain resistance?
Due to:
• mutation of ribosomal receptor site
• modification of the receptor
• enzymatic inactivation of drug
- Most Gram-negative aerobes & enterococci are intrinsically resistant
- Cross-resistant with macrolides
Which drugs are considered Streptogramins?
1) Quinupristin
2) Dalfopristin
What is the MOA of Streptogramins?
Bind to separate sites on 50S becterial ribosome
What is the clinical application of Streptogramins?
• Restricted to treatment of infections caused by drugresistant
Staphylococci or VRE
Which cytochrome does Streptogramins inhibit?
CYP 3A4
What is the MOA of Linezolid?
- Inhibits formation of 70S initiation complex
* Binds to unique site on 23S ribosomal RNA of 50S subunit
What is important to rmbr about the PK of Linezolid?
- Oral & IV
- Weak reversible inhibitor of MAO
What are the contraindications of Linezolid?
• Reversible, nonselective inhibitor of MAO -> potential
to interact with adrenergic and serotonergic drugs
What is the use of Fidazomicin?
• Activity against Gram-positive aerobes and
anaerobes especially Clostridia
What is the MOA of Fidaxomicin?
• Inhibits bacterial protein synthesis by binding to RNA
polymerase
What is the benefit of Fidaxomicin?
Recurrence of C.Diff is greatly reduced
