Aminoglycosides, Monobactams and Carbapenem Flashcards
What are the two common monobactams and how are they administered?
aztreonam: parenteral
Trigemonam: orally
Spectrum for monobactams
Gram negative and pseudomonas
CIA
Indications for monobactams
septicaemia
meningitis
peritonitis
E.coli multiresistant, Uti
Common carabapenems
Imiperem
Meroperem
what can we combine imiperem with to increase the half life, and what is the half life normally?
1-2 h normally
if we use cilastatin, we can increase the halflife as it will inhibit dihydropeptidase
What does the amount of amino groups mean for aminoglycosides
more amino groups means more accumulation and especcially in ear and kidney (phosphatidili inositol)
oral absorption of aminoglycosides?
bad - hydrophilic
excreted by the kidney without metabolic change
which aminoglycosides are the natural ones, and what is the name of the fungi?
streptomycin neomycin spectinomycin - aminocyclitol kanamycin tobramycin
by streptomyces spp
semisynthetic aminoglycoside and fungi
amikacin
streptomyces spp
synthetic aminoglycoside
gentamicin
micromonospora spp
mechanism of action of aminoglycosides
30s ribosomal ubuint - produces false proteins
needs oxygen and energy to be taken up
RNA structure damage
mode of action - aminoglycosides
bactericidal (spectinomyocin is bacteriostatic)
concnetration dependent
PAE
spectrum of aminoglycosides
gram negativ aerobic and staphylococcus spp
Resistance of aminoglycosides
Ab ovo: anaerobic bacteria and E.coli is spreading
cross resistance, one way
resistance mechanisms of bacteria towards aminoglycosides
plasmids
altering enxymes: acetylation, adenylation
reduced permeability: active transport
aminoglycosides: absorption
PO or parenteral
intramammary, intrauterine or into abscesses
aminoglycosides: distribution
not very good - hydrophilic
used to treat meningitis - BBB
cats are sensitive, dont treat cts abscesses
aminoglycoside accumulation
in kidney cortec and ear
aminoglycosides toxicity
one of the most toxic AB. neomycin most toxic
predisposing factors: aminoglycosides
kidney problems
hydration state
operation
combining muscle relaxants and aminoglycosides?
dont do it: neuromuscular blockade (myosthenia grais like symptoms) Ach release is inhibitied
aminoglycosides indications
respiratory infections GI UTI mastitis dermatitis - topical septicaemia - combination
aminoglycoside antibiotic drugs
streptomycin neomycin gentamicin spectinomycin apramycin tobramycin amikacin
good aminoglycosides against pseudomonas spp
amikasin
gentamycin
tobramycin
streptomycin
- use
- indication
- duration
- application
Don’t use alone Used in combinations w/penicillins TTC Used against streptococcus, mastitis Duration is 86h IM or SC (intramammary)
Neomycin
- use
- indication
- synergist
Used alone Used in combinations w/penicillins – if it is life threathening, more potent effect Mastitis – topical Biosol – GI Parenteral – not frequently used Synergistic strepto + penicillin - Different bacteria is targeted - Penicillin – cell wall - Aminoglycoside – can be transported inside bacteria
Gentamicin
- use
- application
- indication
Alone w/ penicillin – CIA (amoxicillin) per os, parentera or topical mastitis UTI Ear, eye drops = topical GI – per os
spectinomycin
- mode of action
- indications
- use
- application
Bacteriostatic
Mycoplasma – good against it
Used alone and in combination with lincomycin (anaerob + aerob)
Per os and parenteral
apramycin
- species
- application
- indication
Bioavailability is better wit oral administration
Swine
Per os
GI or respiratory
tobramycin
- info
- application
- indication
Most active
Toxic
Topical, parenteral
Ear, eye
amikacin
- toxic?
- ow long can it be used?
- indications?
One of the most active Slightly toxic Parenteral Very safe, can be used for two weeks Good against MRSA, MRSP
