Antimicrobial Chemotherapy Flashcards
2 sites of action if antibiotics
- cell wall synthesis
- Nucleic acid synthesis
- Protein synthesis
Examples of antibiotics that inhibit cell wall synthesis
Penicillin and cephalosporins
Examples of antibiotics that inhibit protein synthesis
Gentamicin and erythromycin
Examples of antibiotics that inhibit nucleic acid synthesis
trimethoprim and ciprofloxacin
How do Beta lactams work
Disrupt peptidoglycan synthesis and inhibit PBP’s
Examples of glycopeptides
Vancomycin and teicoplanin
When do glycopeptides act?
Stage earlier to beta lactams, inhibiting assembly of precursor
Do glycopeptides act only on gram positive or gram negative and why?
Gram positive as they cannot penetrate gram negative cell wall
Problem with Vancomycin?
Toxicity - otoxicity, nephrotoxicity and rashes
Aminoglycosides
Gentamicin
What are not sensitive to aminoglycosides
Streptococci
What are aminoglycosides usually used for
Serious gram negative (coliform) infections
Macrolides
Erythromycin and clarithromycin
What are macrolides used for
Gram positive infections for those allergic to penicillin’s
Linezolid
Protein synthesis
MRSA
Daptomycin
Gram positives and MRSA
What do trimethroprim and sulphamethoxazole inhibit?
Purine synthesis
co - trimoxazole
Less likely to cause c diff
Trimethroprim
UTI
Fluoroquinolones
Ciprofloxacin inhibit DNA synthesis more directly
Gram negative - pseudomonas
Why can fluoroquinolones not be used in children?
Interfere with cartilage growth
Co-amoxiclav
Amoxicillin and clavulanic acid to combat beta lactamase resistance
What is flucloxacillin resistant to?
Beta lactamase and is antistaphylococcal
