Beta Lactam Antibiotics Flashcards
How is penicillin administered?
IV
Oral form = penicillin V (but rarely used)
Which 3 infections does penicillin treat?
Which is the main one?
Streptococcus (first line)
Clostridium
Neisseria
What is the first line treatment for streptococcal infections?
Penicillin
Which 5 infections does amoxicillin treat?
Streptococcus Enterococcus Clostridium Neisseria Haemophilus
How is amoxicillin administered?
Oral
Which 2 infections does flucloxacillin treat?
What can it NOT treat AT ALL?
Staph. aureus (not MRSA)
Streptococcus
CANNOT treat any gram negative organisms
How is flucloxacillin administered?
Oral
Give 2 examples of β-lactamase inhibitors.
Clavulanic acid
Tazobactam
Give 2 examples of combination therapy, combining β-lactams and β-lactamase inhibitors.
C-amoxiclav (amoxicillin + clavulanic acid)
Tazocin (piperacillin + tazobactam)
Which 2 infections are β-lactamase inhibitors useful for?
Gram negative bacteria
Staph. aureus
Which infections is co-amoxiclav used for?
Any EXCEPT pseudomonas
How is co-amoxiclav adminstered?
Oral
Which infections is tazocin used for?
Any infection
How is tazocin administered?
IV
What are the disadvantages of β-lactamase inhibitors? (2)
There are many β-lactamases that are NOT inhibited
Resistance is increasing
How is ceftriaxone administered?
IV
Which 7 infections is ceftriaxone used for?
Streptococcus Staphylococcus E. coli & other coliforms Neisseria Haemophilus Bacteriodes Clostridium
NOTE: this is everything EXCEPT enterococcus and pseudomonas
How is meropenem administered?
IV
Which infections is meropenem used for?
Any bacteria
BUT only after all other antibiotics have failed - avoid using meropenem to avoid resistance developing
How is aztreonam administered?
IV
Which 5 infections is aztreonam used for?
Which infections can it NOT be used for AT ALL? (2)
E. coli Other coliforms Neisseria Haemophilus Pseudomonas
CANNOT be used for any gram positive infections/anaerobic gram negative infections
How do you treat MRSA (methicillin resistant staph aureus)?
NOTE: this is NOT a beta lactam antibiotic. What sort of antibiotic is it?
Vancomycin
Glycopeptide antibiotic
Describe the mechanism of action of vancomycin. (3)
- Inhibits cell wall formation in gram positive bacteria
- No action against gram negative bacteria
- Not reliant on penicillin binding proteins, therefore effective against resistant organisms
Describe the mechanism of action of beta lactam antibiotics. (3)
- Beta lactam ring is an analogue to the peptidoglycan cell wall
- Inhibits cross linking of the cell wall, as enzymes involved in this preferentially bind to beta lactams
- This causes lysis of the bacterial cell
How is vancomycin administered?
What is one situation in which you would give it differently?
IV
NOTE: oral to treat C. diff (because it stays inside the gut)
Which infections are treated with vancomycin?
Gram positives, e.g. Streptococcus Enterococcus Clostridium Staphylococcus (including MRSA)
List 3 adverse effects of vancomycin.
- Nephrotoxicity
- Red man syndrome
- Ototoxicity
List 4 adverse effects of beta lactam antibiotics.
Give 3 examples of each of these.
GI toxicity (vomiting; diarrhoea; cholestasis)
Hypersensitivity (type 1; type 4, interstitial nephritis)
Infection (candidiasis; C. diff; resistant bacteria)
Rare reactions (seizure; haemolysis; leukopenia)
Which penicillins are oral?
Which penicillins are IV?
Oral penicillins: Penicillin V Amoxicillin Flucloxacillin Co-amoxiclav
IV penicillins:
Benzyl-penicillin
Tazocin
