Glycopeptides - Vancomycin Flashcards
What is vancomycin used for?
1) Gram Positive infection e.g. Endocarditis
2) Penicillin allergy or Resistance (MRSA)
3) Antibiotic associated colitis - C.diff (2nd line when metronidazole doesn’t work)
How does vancomycin work?
Vancomycin stops growth and cross linking of peptidoglycan chains ———> Inhibits synthesis of cell wall of GRAM POSITIVE bacteria.
What are the side effects of vancomycin?
- infalmmation of vein (thrombophlebitis)
- anaphylactoid reaction (Red man syndrome - erythema, hypotension, bronchospasm)
- hypersensitivity reaction
- nephrotoxicity
- ototoxicity (tinnitus/hearing loss)
- blood disorders e.g. neutropenia / thrombocytopenia)
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A side effect of vancomycin is an anaphylactoid reaction - what is this characterised by?
Red man syndrome:
- erythema
- bronchospasm
- hypotension
(anaphylactoid syndrome is not the same as an allergic reaction as it is not antigen mediated)
What precautions should you take with vancomycin?
- dose reduction in renal impairment and elderly (increased risk of hearing impairment)
- carefully monitor plasma drug concentration and adjust dose accordingly to avoid toxicity
What are the drug interactions of vancomycin?
Increased risk of nephrotoxicity / otoxicity with:
- Aminoglycosides (gentamicin)
- loop diuretics
- ciclosporin
What bacteria is vancomycin affective against?
Gram positive aerobes and anaerobes!!!
what is the typical dose and route of vancomycin for C.diff?
Vancomycin for C.diff:
125 mg / 6hrly / orally
for 10 - 14 days
why must vancomycin be given as a slow infusion over 60 minutes and not as an IV bolus or IM?
- reduce risk of anaphylactoid reaction (Red man syndrome)
How do you montior vancomycin safety?
- daily renal function
- regular FBC (prolonged used can cause blood disorders e.g. neutropenia, thrombocytopenia)
