Aminoglycosides Flashcards
Aminoglycosides EXAMPLES?
Amikacin,Gentamicin,neomycin,streptomycin,tobramycin =
Serum aminoglycoside concentration - Must be determined for who?? Especially needs determining in patients with which parameters? What can aminoglycosides cause? Mow often do we need to measure gentamicin concentration?
- Measured in all patients receiving parenteral aminoglycosides
- Must be determined in obesity,high doses,cystic fibrosis and elderly
- Aminoglycosides can cause renal toxicity
- Measure serum gentamicin concentration after 3 or 4 doses, then every 3 days and after a dose change - more frequently in renal impairment
- Measure 1 hour after dose and just before next dose
For peak concentration( genera land endocarditis)
5-10 mg/l - general
Endocarditis - 3-5mg/l - because we co prescribe
(For multiple daily dose regimen)
Trough serum conc less than 2 mg/l - trough serum is the concentration in the blood immediately before the next dose of drug what bout fro endocarditis
Endocarditis - we want to stay less than 1mg/l
Other key points!!!
- if the trough is too high what do we do to the dose?
If the peak is too high what do we do to the dose?
If there is renal impairment what do we do to the dose
If there is SEVERE renal impairment what do we do to the dose?
We avoid concomitant use with what kinds of drugs?
MHRA warning is associated with what specifically?
What are the interactions that cause ototoxicity?
What is the main contraindication?
What about obese patients??
Dose adjustments -
Trough too high - increase dose interval
Peak too high - decrease dose
Renal impairment-
Renal impairment - increase dose interval
Severe renal impairment - reduce dose as well
Avoid concomitant use of nephrotoxic drugs - because it causes renal toxicity
MHRA WARNING - Ototoxicity associated
Interaction with ototoxicity -
- Cisplatin
- Loop diuretics
- Vancomycin
- Vinca alkaloids (vinblastine,vincristine,vindeserine,vinflunine)
Further interactions - drugs that cause renal impairment - like nsaids,acei,arbs,metformin
Contraindication - Myasthenia Gravis
- Avoided in pregnancy due to risk of auditory or vestibular nerve damage
- Monitor serum concentration
Obese patients -
Use ideal body weight based on height to calculate parenteral dose
Aminoglycoides Infusions
Changing the sites of the infusion can regularly minimise the frequency and severity of thrombophlebitis- Quick infusion can lead to cardiac shock so avoid this. Infusions can also lead to cardiac shock (hypotension) and red man’s syndrome so caution!!!!. Infusion can also cause pain and thromphlebitis - where any infusion related irritation - give anaesthetic !!!
VANCOMYCIN CONCENTRATION - Prophylactically administered to a patient during surgery what would we expect trough serum conc - high risk of MRSA
THOUGH TROUGH SHOULD BE 10-20 - Trough conc of 15-20 is recommended to cover susceptible pathogethern with MIC Greater than or equal to 1mg/l
Glycopeptides - examples?
How should vanco be given? Due to what?
Who should it be avoided in?
What should trough conc be ?
What does it cause
Glycopeptides:
Dalbancin,teicoplanin,telavancin,vancomycin
-vancomycin should only be given parenterally for systemic infections due to reduced absorption with oral intake
-Should be avoided in pregnancy unless benefit outweighs the risk
-initial doses based on body weight,then dose adjustment based on serum vancomycin concentrations
- Trough concentration should be 15-20 mg/l
Can cause ototoxicity and nephrotoxicity
SAME interactions as aminoglycosides
Side effects:
-Redman syndrome
Severe cutaneous adverse reactions SJS
-Blood dyscrasias: Agranulocytosis,eosinophilia,neutropenia
Cardio genie shock on rapid intravenous injection
Risk of anaphylactic reactions at infusion sites - avoid rapid infusion and rotate site
Glycopeptides
Avoid concomitant use of nephrotoxic drugs - because it causes renal toxicity
MHRA WARNING - Ototoxicity associated
Interaction with ototoxicity -
- Cisplatin
- Loop diuretics
- Vancomycin
- Vinca alkaloids (vinblastine,vincristine,vindeserine,vinflunine)
Further interactions - drugs that cause renal impairment - like nsaids,acei,arbs,metformin
Contraindication - Myasthenia Gravis
- Avoided in pregnancy due to risk of auditory or vestibular nerve damage
- Monitor serum concentration
Obese patients -
Use ideal body weight based on height to calculate parenteral dose
