Anti microbial Mechanism of Action Flashcards
same MOA as PCN but narrow spectrum
penicillinase resistant d/t bulky R group
Dicloxacillin
Nafcillin
Oxacillin
same MOA as PCN but wider spec
may combine w/ clavulanic acid to protect against B lactamse
Amoxicillin- greater oral availability
Ampicillin
B lactam drugs that inhibit cell wall synthesis but are less susceptible to penicillinase
bactericidal
Cephalosporins generations I-V
inhib cell wall peptidoglycan formation via binding DalaDala of cell wall precursors
bactericidal, not susceptible to B lacatamase
Vancomycin
broad spec B lactamase resistant carbapenems
always given w/ ____ to inhib renal dehydropeptidase I in order to lower inactivation of drug in renal tubules
Imipenem, Meropenem, Ertapenem, Doripenem
Cilastatin- inhibits renal inactivation of drug
B lactamase inhibitors
Clavulanic acid
Sulbactam
Tazobactam
blocks peptidyltransferase at 50S, bacteriostatic
Chloramphenicol
bind PBP’s to block transpeptidase cross linking of peptidoglycan in cell wall
activate autolytic enzymes
PCN G- i.v., i.m.
PCN V- oral
same MOA as PCN but extended spec
anti pseudomonals
use with B lactamase inhibitors
Piperacillin
Ticarcillin
monobactam less susceptible to B lactamase
prevents peptidoglycan cross linking via binding to PBP3
synergistic w/ aminoglycosides
not cross allergic with PCN
Aztreonam
bacteriostatic, bind 30S to prevent tRNA attachment, limited CNS penetration
do NOT take with milk or antacids or Fe
Tetracycline, Doxycycline, Minocycline
inhib protein synthesis via binding 50S to prevent formation of initiation complex
Linezolid (Oxazolidinones)
bactericidal, bind 30S initiation complex causing mRNA misreading, block translocation
require O2 for uptake
Aminoglycosides: Gentamicin, Neomycin, Amikacin, Tobramycin, Streptomycin
blocks translocation at 50S, bacteriostatic
Clindamycin
forms toxic free radical metabolites in bacterial cell that damage DNA, bactericidal, anti protozoal
Metronidazole
inhib protein synthesis via blocking translocation by binding 23S rRNA of 50S, bacteriostatic
Macrolides: Azithromycin, clarithromycin, erythromycin
lipopeptide that disrupts c.m. of GPC
Daptomycin
inhib folate synthesis via PABA anti metabolites which inhib dihydropteroate synthase, bacteriostatic alone
Sulfonamides: Sulfamethoxazole (SMX), sulfisoxazole, sulfadiazine
inhib prokaryotic topoisomerase II & IV, bactericidal
Fluoroquinolones: Ciprofloxacin, Norfloxacin, Levofloxacin, Ofloxacin, Moxifloxacin, Gemifloxacin, Enoxacin
inhibit DNA dependent RNApol
Rifampin
Rifabutin
inhib bacterial dihydrofolate reductase, bacteriostatic
Trimethoprim
decreases synthesis of mycolic acids, bacterial catalase peroxidase needed to convert it to active form
Isoniazid
prodrug converted to active pyrazinoic acid to treat MTB
Pyrazinamide
lowers carb polymerization of mycobacterium cell wall by blocking arabinosyltransferase
Ethambutol
binds ergosterol forming pores that allow electrolyte leakage from fungi
Amphotericin B
inhibits DNA & RNA biosynthesis by converting to 5-fluorouracil by cytosine deaminase
Flucytosine
same MOA as Amphotericin B (forms pores), topical use only
Nystatin
inhib fungal sterol synth by inhib cytochrome P450 which converts lanosterol to ergosterol
Azoles: Clotrimazole, fluconazole, itraconazole, ketoconazole, miconazole, voriconazole
inhib fungal enzyme squalene oxidase
Terbinafine
inhib cell wall synth by inhib synth of B-glucan
Echinocandins: Anidulafungin, Caspofungin, Micafungin
interferes w/ microtubule formation - disrupts mitosis, deposits in keratin tissues
Griseofulvin
anti-mite/louse tx that inhibits acetylcholinesterase
Malathion
blocks detoxification of heme into hemozoin - heme builds up and is toxic to plasmodia
Chloroquine
selectively inhib viral DNApol
does not require viral kinase phosphorylation
Cidofovir
anti protozoan therapy
Pyrimethamine, suramin, melarsoprol, nifurtimox, sodium stibogluconate
anti-mite/louse tx that blocks Na+ channels causing neurotoxicity
Permethrin
anti-mite/louse tx that blocks GABA channels causing neurotoxicity
Lindane
inhibit influenza neuraminidase leading to lowered release of progeny virus
Oseltamivir- oral
Zanamivir- inhaled
5’ monophosphate formed by CMV viral kinase, guanosine analog, triphosphate formed by cell kinases, selectively inhib viral DNApol by chain termination
Ganciclovir
viral DNA/RNApol inhibitor & HIV reverse transcriptase inhibitor
binds to pyrophosphate-binding site of enzyme
no activation by viral kinase required
Foscarnet
guanosine analogs monophosphorylated by HSV/VZV thymidine kinase only in infected cells
triphosphate is formed by cell enzymes
selectively inhib viral DNApol by chain termination
Acyclovir, Famciclovir, Valacyclovir