ANTIBIOTIC PHARMACOLOGY Flashcards
what type of antibiotic is amoxicillin?
a beta lactam
what is amoxicillins moa?
it binds to penicillin binding protein 1A in bacterial cell walls and inactivates it, preventing the cross-linking of peptidoglycan strands and inhibiting bacterial cell wall synthesis
what can amoxicllin be given with to overcome bacterial antibiotic resistance?
cluvulanic acid (a beta lactamase inhibitor)
is amoxicillin broad or narrow spectrum?
broad spectrum
active against a wide range of gram positive and limited range of gram negative organisms
is methicillin broad or narrow spectrum?
narrow spectrum
+
what type of antibiotic is methicillin?
beta lactam
what is methicillins moa?
inhibits bacterial cell wall synthesis by inhibiting of the transpeptidase enzyme used by bacteria to cross-link the peptide used in peptidoglycan synthesis in th cell walls of gram-positive bacteria
what is cefurozimes moa?
inhibits cell wall synthesis leading to bacterial lysis
what type of antibiotic is cefuroxime?
cephalosporin
can cefuroxime cross the blood-brain barrier?
yes
what type of antibiotic is benzylpenicillin?
a beta lactam
is cefuroxime broad or narrow spectrum?
broad
is benzylpenicillin broad or narrow spectrum?
broad (but mostly +)
what is benzylpenicillins moa?
binds to penicillin binding proteins which causes inhibition of cell wall synthesis
may also inhibit action of bacterial autolysin inhibitor
what type of antibiotic is oxytetracycline?
tetracycline
what s oxytetracyclines moa?
inhibiting of bacterial cell growth by binding to 30S subunit of the ribosome preventing tRNA from binding to the A site - inhibiting translation
is oxytetracycline broad or narrow spectrum?
broad spectrum
what type of antibiotic is erythromycin?
a macrolide
what is erythromycins moa?
50S subunit inhibition, blocking translocation and inhibiting protein synthesis
is erythromycin broad or narrow spectrum?
broad spectrum
what type of antibiotic is gentamicin?
aminoglycoside
is gentamicin broad or narrow spectrum?
broad
what is genatmycins moa?
inhibiting 30S ribosomal subunit, inhibiting protein synthesis
whats a major side effect of gentamicin?
significant ear and kidney damage
is rifampicin broad or narrow spectrum?
broad
what is rifampicins moa?
inhibits DNA-deendant RNA polymerase leading to suppression of RNA synthesis and cell death
what is rifampicin restricted to treating and why?
mycobacterial infections due to the emergence of resistant bacteria
what is trimethoprims moa?
inhibits reduction of dihydrofolic acid to tetrahydrofolic acid - inhibiting bacterial DNA synthesis
what is trimethoprim used to treat?
UTIs and bronchitis
what is trimethoprim?
a folate antagonist
what type of antibiotic is sulfamethoxazole?
a sulfonamide
what is sulfamethoxazole used to treat?
bronchitis, prostatitis and UTIs
what is sulfamethoxazoles moa?
competes with PABA in binding to dihydrofolate synthesise, causing inhibition of dihydrofolate synthetase and inhibiting synthesis of tetrahydrofolic acid
why are trimethoprim and sulfamethoxazole often used in combination?
as they target the same pathway and their synergistic effects reduce the development of bacterial resistance
what type of antibiotic is vancomycin?
a glycopeptide
what is the moa of vancomycin?
inhibition of NAM and NAG peptide subunits into the peptidoglycan matrix
is vancomycin broad or narrow spectrum?
narrow
gram positive
what type of drug is colistin?
a polymyxin antibiotic agent
is colistin broad or narrow spectrum?
narrow
gram negative bacilli
what is colistins moa?
disrupting the bacterial cell membrane, change its permeability
why are polymyxins sometimes used now (they faded out for a while)?
due to emergence of multi-drug resistant gram negatve bacteria
what type of antibiotic is ciprofloxacin?
a quinolone
is ciprofloxacin broad or narrow spectrum?
broad
what is the moa of quinolones?
inhibition of topoisomerase 2 (DNA gyrase) and topoisomerase 4 which are required for bacterial DNA reslication, transcription, repair, recombination etc
what type of drug is fusidic acid?
a bacteriostatic antibiotic
what is fusidic acids moa?
inhibition of the translocation of the elongation factor G from ribosomes, leading to inhibition of protein synthesis
what type of antibiotic is ampicillin?
a beta lactam
what is ampicillins moa?
interference with cell wall synthesis by attachment to penicillin-binding proteins (PBPs), inhibition of cell wall peptidoglycan synthesis and inactivation of inhibitors to autolytic enzymes.
is ampiciliin broad or narrow spectrum?
broad
what type of antibiotic is phenoxymethyl penicillin?
a beta lactam
what is phenoxymethyl penicillins moa?
kills bacteria through binding of the beta-lactam ring to DD-transpeptidase, inhibiting its cross-linking activity and preventing new cell wall formation
what type of antibiotic is flucloxicillin?
beta lactam
what is flucloxacillins moa?
By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, flucloxacillin inhibits the third and last stage of bacterial cell wall synthesis.
is flucloxacillin broad or narrow spectrum?
narrow - gram positive
what type of antibiotic is clindamycin?
a macrolide
what type of anitbiotic is chloramphenicol?
macrolide
what type of antibiotic is oxazolidinone?
macrolide
what type of antibiotic is streptomycin?
aminoglycoside