Antibiotics Flashcards
Drugs by Target: Good Summary Image: http://www.nature.com/nrd/journal/v12/n5/images/nrd3975-f1.jpg Good Review: http://www.nature.com/nrd/journal/v12/n5/full/nrd3975.html What is the mechanism? (synergize or antagonize, bacteriostatic or bacteriocidial, selective toxicity) what spectrum of activity? (ex. gram negative rods) what side effects?
mechanism: isoniazid (IHN)
inhibits mycolic acid synthesis
spectrum of activity: isoniazid
mycobateria
side effects: isoniazid
liver toxicity
neuro: administered with pyrodoxine to prevent toxicity
prophylaxis: dental work and heart protection
amoxicillin
prophylaxis: joint replacement
cefazolin
ethambutol
bacetiostatic for TB and atypical mycobacteria, blocks links between mycolic acid and peptidoglycan
metronidazole
batericidal for anaerboic bacteria
polyene
antifungal drugs that block ergosterol
azoles: mechanism
topical antifungals that block ergosterol differently than polyenes
toxic due to inhibition of P450
what drug class: fluconazole, ketococonazole, voriconazole, posaconazole, and itraconazole
azoles, topical antifungals
mechanism: amphotericine B
poleyen antifungal with fungicidal action against ergosterol
side effects: amphotericine B
renal toxicity (chills, fever, nausaea, vomitting)
mechanism: Rifampin
bacteriostatic or cidal depending on bacteria
blocks mRNA transcription
spectrum of activity: Rifampin
meningitis, prosthetic valve treatment
side effects: Rifampin
benign, orange sweat and quick resistance
Rifabutin
aginst mycobacterium avium-intracellulare in AIDs patients
Fidaxomycin
inhibits RNA pol of C. diff, spares normal flora of colon
mechanism: trimethoprim
bacteriostatic, inhibits nucleotide synthesis, acts on DHFR
specificity: trimethoprim
used primarily to treat urinary tract infections
also prophylaxis of pneumonia and shigellosis
toxicity: trimethroprim
bone marrow toxicity
mechanism: sulfonamides
bacteriostatic, inhibits nucleotide synthesis, acts on PABA synthesis
spectrum: sulfonamides
broad, urinary tract e. coli, h. flu in children, shigellosis, nocardiosis, chnacroid
toxicity: sulfonamides
erythtrema multiformis
Stevens-Johnson Syndrome
Toxic epidermal necrolysis
photosensitivity/ drug rash
mechanism: streptogramnins
bacteriostatic (alone)
acts on 50S to
cause premature release of a polypeptide, different from all similar drugs
spectrum: streptogramnins
quinopristin and dalfopristin treat blood stream infections and reistant streps
toxicity: streptogramnins
itching and irritation at infusion site
mechanism: telithromycin
acts on 50S, acts similar to macrolides without cross reaction (bacteriostatic)
spectrum: telithromycin
(ketek) used against community aquired bacteria
especially those resistant to macrolides (azithromycin, erythromycin, clarithromycin)
toxicity: telithromycin
pseudomembranous colitis (clostridium difficle overgrowth)
mechanism: linezolid
bacteiro-static or cidal depending on strain
blocks 50S RNA
spectrum: linezolid
bacteriostatic against enterococci and staphylococci
bactericidal against pneumococci
toxicity: linezolid
not common
mechanism: clindamycin
bacteriostatic, acts on 50S to block peptide bond formation
spectrum: clindamycin
anaerobes
toxicity: clindamycin
pseudomembranous colitis due to c. diff overgrowth
mechanism: macrolides (azithromycin, erythromycin, clarithromycin)
bacteriostatic:
bind to 50S and
prevent release of uncharged tRNA
spectrum: macrolides (azithromycin, erythromycin, clarithromycin)
broad
azith: genital tract and resp
erythro: similar but worse side effects
clarithromycin: heliobacter and mycobacterium
toxicity: macrolides (azithromycin, erythromycin, clarithromycin)
? bacterial overgrowth
mechanism: chloramphenicol
bacteriostatic: binds to 50s and blocks action of peptidyl peptidase (in mitochondria too)
spectrum: chloramphenicol
bacteriostatic: some, such as S. Tyhphi
bacteriocidal: meningitis H. flu, s. pneumoniae, n. meningitidis
toxicity: chloramphenicol
gray baby syndrome, bone marrow suppression, asplastic anemia
due to suppression of mitochondrial ribosomes
mechanism: tetracycline
baceriostatic drugs that
bind to 30S and
prevent release of tRNA from acceptor site, selective uptake
spectrum: tetracycline
very broad
doxycycline, minocycline, oxytetracycline
toxicity: tetracycline
- supression of normal flora in gut and vagina
- brown staining of children’s teeth
- chelate iron
- photosensitivity and rash
doxycycline: class
tetracycline drug
minocycline: class
tetracycline drug
oxytetracycline: class
tetracycline drug
mechanism: aminoglycosides
act on 30S to block intiation
spectrum: aminoglycosides
gram negative rods
streptomycine: TB, tularemia, plague, brucellosis
gentamicin: gram negative infections
toxicity: aminoglycosides
- toxic to kidneys
- toxic to vestibular portion of CN VIII
* poor penetration to CSF, injections are necessary
mechanism: bacitracin
cell wall, bactericidal, blocks lipid carrier of peptidoglycan
spectrum: bacitracin
skin infections
toxicity: bacitracin
highly, must be administered topically
mechanism: cycloserine
cell wall, analogue of D-alanine
spectrum: cycloserine
TB, second line
toxicity: cycloserine
neurologic side effects due to its penetration of CNS and binding to glutamine channels
azetronam: class
monobactam, beta lactam good against gram negative rods
mechanism: vancomycin
baceriocidal , glycopeptide that inhibits transpeptidation
spectrum: vancomycin
bacterocidal against gram positive bacteria
toxicity: vancomycin
red man syndrome
mechanism: carbapanems
cell wall, beta lactam, bactericidal
spectrum: carbapanems
very broad: gram positive, gram negative, and anerobes
toxicity: carbapanems
well tolerated with few resistant strains
cefazolin: class
cephalosporin beta lactam
cephalexin: class
cephalosporinbeta lactam
cefuroxinme: class
cephalosporin beta lactam
cefoxitin: class
cephalosporin beta lactam
cef___: class
cephalosporinbeta lactam
cephalosporins: mechanism
bactericidal drugs that block cross linking transpeptidase of cell walls
cephalosporin: spectrum
very broad, generations formulated for specialized targets
cephalosporin: toxicity
much lower hyersensitivity
amoxicillin: class
penicillin
ampicillin: class
penicillin
mechanism: penicillins
bacteriocidal
cell wall, block transpeptidation
spectrum: penicillins
penicillin G: gram positive cocci
ampicillin/ amoxicillin: gram negative rods
toxicity: penicillins
may cause hypersensitivity, anaphylaxis or drug rash