microbio drugs Flashcards
penicillin
CW synth inhibitor - B-lactam
binds penicillin-binding proteins –> peptidoglycan cross linking
bactericidal
gram (+), gram (-), spirochetes
AE: hypersensitivity, hemolytic anemia
penicillinase sensitive (B-lactamase)
amoxicillin
ampicillin
CW synth inhibitor - B-lactam
binds penicillin-binding proteins –> peptidoglycan cross linking
extended spectrum penicillin - H influenzae, H pylori, E coli, Listeria, Proteus, Salmonella, Shigella, enterococci (HHEELPSS)
AE: hypersensitivity, rash, pseudomembranous colitis
penicillinase sensitive - use w/ clavulanic acid
methicillin
dicloxacillin
naficillin
oxacillin
CW synth inhibitor - B-lactam
binds penicillin-binding proteins –> peptidoglycan cross linking
narrow spectrum penicillin - S aureus
AE: hypersensitivity, interstitial nephritis
penicillinase resistant
piperacillin
ticaricillin
CW synth inhibitor - B-lactam
binds penicillin-binding proteins –> peptidoglycan cross linking
Pseudomonas. gram (-) rods
AE: hypersensitivity
penicillinase sensitive - use w/ B-lactamase inhibitor
clavulanic acid
sulbactam
tazobactam
B-lactamase inhibitors
added to PCN abx to protect from destruction by penicillinase
cefazolin, cephalexin
cefoxitin, cefaclor, cefuroxime
ceftriaxone, cefotaxime, cefazidime
ceftaroline
(-) CW synthesis - interfere w/ peptidoglycan cross linking
B-lactam, less susceptible to penicillinases
bactericidal
H influenzae, Enterobacter, Neisseria, Proteus, E coli, Klebsiella, Serratia serious gram (-) resistant to other B-lactams Pseudomonas
AE: hypersensitivity, AI hemolytic anemia, disulfiram-like rxn, vit K deficiency, increase nephrotoxicity of aminoglycosides
doripenem ertapenem imipenem meropenem (carbapenems)
CW synth inhibitor - B-lactam
binds penicillin-binding proteins –> peptidoglycan cross linking
broad spectrum
AE: GI distress, skin rash, CNS toxicity (seizures)
*use limited
always use w/ cilastatin to decrease inactivation in renal tubules
B-lactamase resistant
aztreonam
monobactam
binds PBP3 –> prevents peptidoglycan cross linking
less susceptible to B-lactamases
synergystic w/ aminoglycosides
no cross allergenicity w/ penicillins
gram (-) rods only
AE: usually nontoxic, occasional GI upset
vancomycin
(-) peptidoglycan synthesis by binding D-ala D-ala portion of CW precursors
gram (+) only - MRSA, S epidermidis, Entercoccus, C diff
AE: nephrotoxicity, ototoxicity, thrombophlebitis, red man syndrome (flushing)
not susceptible to B-lactamase
gentamicin neomycin amikacin tobramycin streptomycin (aminoglycosides)
bind 30s subunit –> irreversible inhibition of initiating complex, misreading of mRNA, blocks translocation
require O2 for uptake
bactericidal
severe gram (-) rod infxns
synergistic w/ B-lactams
neomycin for bowel surgery
AE: nephrotoxicity, neuromuscular blockade, ototoxicity, teratogen
tetracycline
doxycycline
bind 30s –> prevent attachment of aminoacyl tRNA
GI absorption deceased w/ calcium or magnesium ingestion, or iron containing preparations
Borellia burgdorferi, M pneumoniae, Rickettsia, Chlamydia
acne
AE: GI distress, discoloration of teeth & (-) bone growth in children, photosensitivity
chloramphenicol
blocks peptidyltransferase at 50s
bacteriostatic
meningitis (H influenzae, N meningitidis, S pneumoniae), RMSF
AE: anemia (dose dependent), aplastic anemia (dose independent), gray baby syndrome
*use limited due to tox.
clindamycin
blocks peptide transfer (translocation) at 50s
bacteriostatic
anaerobic infxns in aspiration PNE, lung abscesses, & oral infxns (anaerobic infxns above diaphragm)
invasive group A strep
AE: pseudomembranous colitis, fever, diarrhea
linezolid (oxazolidinones)
inhibits protein synth at 50s, prevents formation of initiation complex
gram (+), MRSA, VRE
AE: BM suppression, peripheral neuropathy, serotonin syndrome
azithromycin
clarithromycin
erythromycin
(macrolides)
block translocation, bind 23s rRNA of 50s
bacteriostatic
atypical PNE - Mycoplasma, Chlamydia, Legionella
STIs
gram (+) cocci
B pertussis
AE: GI motility issues, arrhythmia - prolonged QT, acute cholestatic hepatitis, rash, eosinophilia, increases conc of theyophillines & oral anticoag, inhibit cyt P450
trimethoprim
inhibits Dihydrofolate Reductase
bacteriostatic
in combo w/ sulfonamides (TMP-SMX)
UTI, Shigella, Salmonella, Pneumocystis prophylaxis, toxoplasmosis prophylaxis
AE: megaloblastic anemia, leukopenia, granulocytopenia
supplement w/ folic acid
sulfonamides
inhibit folate synth - PABA antimetabolites inhibit Dihydropteroate Synthase
bacteriostatic alone, bactericidal w/ TMP
gram (+), gram (-), Nocardia, Chlamydia, UTI
AE: hypersensitivity, hemolysis in G6P deficiency, nephrotoxicity - tubulointerstitial nephritis, photosensitivity, kernicterus, displaces other drugs from albumin (warfarin)
dapsone
closely related to sulfonamides
Lepromatous leprosy
ciprofloxacin
fluoroquinolones
inhibit prokaryote Topoisomerase II & IV
bactericidal
cannot take w/ antacids
gram (-) rods of urinary & GI tract, Neisseria, some gram (+)
AE: GI upset, superinfections, skin rash, HA, dizziness, tendonitis or tendon rupture, contraindicated in pregnancy due to cartilage damage
daptomycin
lipopeptide that disrupts cell memb of gram (+) cocci
S aureus skin infxns (esp MRSA), bacteremia, endocarditis, VRE
(not for PNE - inactivated by surfactant)
AE: myopathy, rhabdomyolysis
metronidazole
forms toxic free radical metabolites –> famage DNA
bactericidal, antiprotozal
Giardia, Entamoeba, Trichomonas, Gardnerella, Anaerobes, H pylori
(anaerobic infxns below diaphragm)
AE: disulfiram-like rxn, HA, metallic taste
rifampin
rifabutin
(-) DNA-dependent RNA polymerase
mycobacteria
prophylaxis of H influenzae & N meningitidis close contacts
AE: hepatotoxicity, induce cyt P450, orange body fluids,
monotherapy –> resistance
isonizaid
(-) synth of mycolic acids
req bacterial catalase peroxidase to convert into active metabolite
TB
AE: neurotoxicity (give pyridoxine/B6) , hepatotoxicity, drug-induced lupus
pyrazinamide
uncertain mechanism
prodrug, converted to active metabolite - pyrazinoic acid
TB
AE: hyperuricemia, hepatotoxicity
ethambutol
block arabinosyltransferase –> dec carbohydrate polymerization of CW
TB
AE: optic neuropathy (red-green color blindness)
amphotericin B
binds ergosterol –> pores in membrane –> leakage of electrolytes
serious, systemic mycoses
AE: fever/chills, hypotension, nephrotoxicity, arrhythmias, anemia, IV phlebitis
(hydration dec nephrotox, supplement w/ K & Mg)
nystatin
binds ergosterol –> pores in membrane –> leakage of electrolytes
topical fungal infxns only
oral candidiasis, diaper rash, vaginal candidiasis
flucytosine
conversion to 5-FU –> (-) DNA & RNA synthesis
systemic fungal infxns in combo w/ amphotericin B
(esp cryptococcal meningitis)
AE: BM suppression
fluconazole
itraconazole
ketoconazole
voriconazole
(-) cyt P450 converting lanosterol to ergosterol
local mycoses, less serious systemic mycoses
fluconazole: chronic suppression of cryptococcal meningitis in AIDS pts, candida infxns
itraconazole: blastomyces, coccidioides, histoplasma
AE: (-) testosterone synth = gynecomastia (esp w/ ketoconazole), liver dysfunction
terbinafine
(-) squalene epoxidase
dermatophytoses
AE: GI upset, HA, hepatotoxicity, taste disturbance
anidulafungin
capsofungin
micafungin
(echinocandins)
(-) B-glucan synth = (-) CW synth
invasive aspergillosis, candida
AE: GI upset, flushing
griseofulvin
interferes w/ MT fxn, disrupts mitosis
PO trx of superficial infxns, inhibits growth of dermatophytes
AE: teratogenic, carcinogenic, confusion, HA, increased CYP & warfarin metabolism
