Antibiotics RCOA Flashcards
How are penicillins divided?
Narrow spectrum: Benzyl, Fluclox
Broad: Amox, Amp
Antipsuedomonal: Pip, Ticarcillin
B-lactamase resistant: Fluclox
Why do narrow spectrum penicillins have little activity against gram -ve bacteria?
Gram -ve have outer phospholipid membrane hinders access to cell wall beneath
Why do broad spectrum penicillins have good activity against gram -ve bacteria?
More hydrophobic so pass through pores in phospholipid membrane but inactivated by b-lactamases.
What do antipseudomonal penicillins work against?
Gram positive
Gram negative
Anaerobes
What do most staphylococci produce?
Penicillinase (a B-lactamase)
How is MRSA penicillin resistant?
Changes in its penicillin binding proteins
What are cephalosporins indicated for?
- Penumonia
- Sepsis
- Meningitis
- Surgical prophylaxis
Why is Ceftriaxone given once daily?
Long half life
What are the 3 generations of Cephalosporins?
1- Cefradine: ortho ops
2- Cefuroxime: Gram -ve cover
3 - Ceftriaxone, Cefotaxime: Encourages superinfection
What are carbapenems ineffective against?
- MRSA
- E. Faecalis
- Some strains of pseudomonas
Do Macrolides cause drug interactions?
Potent inhibitor of P450 system
What are ahminoglycosides used for?
Serious gram -ve infections
How do aminoglycosides get into the cell?
Active transport due to being large polar molecules
What are the SE of Metro?
- Rash
- Pancreatitis
- Peripheral neuropathy
