Antibiotics Flashcards
bind penicillin-binding proteins (PBPs), block transpeptidase cross linking of peptidoglycan
Beta-lactams
Beta-lactam, most gram + organisms, plus N. meningitis and syphillus. penicillinase sensitive (a beta-lactamase)
Penicillin G (IV/IM) and V (oral)
Beta-lactam. penicillinase sensitive. combo with clavulonic acid to protect. extended spectrum penicillin.
Amoxicillin (oral) and ampicillin
Beta-lactam. penicillinase resistant. Staph aureus (not MRSA).
oxacillin, nafacillin, dicloxacillin
Extended spectrum Beta0lactams. Pseudomonas and G- rods. penicillinase sensitive
ticarcillin, piperacillin
Beta-lactamase inhibitors
Clavulonic Acid, Sulbactam, Tazobactam (CAST)
BEta-lactams, less susceptible to penacillinase. BActeriacidal. do not cover Listeria, Atypicals, MRSA, and Enterococcus (LAME)
Cephalosporins
Beta lactams, G+ cocci, Proteus, E. coli, Klebsiella pneumonia (PEcK)
1st gen cephalosporins: Cefazolin and cephalexin
Beta-lactams. 1st gen (PEck) plus Haemophilus, Enterobacter, Neisseria, and Serratia (HEN PEcKS)
2nd gen cephalosporins: cefoxitin, cefaclor, cefuroxime
Beta-lactams. serious G- resistant to other beta-lactams. Meningitis, gonorrhea, Pseudomonas
3rd gen cephalosporins: Ceftriaxone (meningitis, gonorrhea), cefotaxime, and ceftazidime (Pseudomonas)
Beta-lactam, increase activity against Pseuomonas and G+.
4th gen cephalosporins: cefepime
Beta-lactam, broad G+ and G-, including MRSA. NOT Pseudomonas
5th gen cephalosporins: ceftaroline
Binds PBPs, penicillimase resistant. G- rods in patients w/Pen allergies or renal insufficiency (Aminoglycosides)
Aztreonam (monobactam)
block peptidoglycan cross linking, broad spectrum, penicillimase resistant. only life threatening infection (CNS toxicity)
Carbapenems: imipenem, meropenen, ertapenem, doripenem
inhibit peptidoglycan formation by binding D-ala D-ala. Multidrug resistant organisms.
Vancomycin
inhibit initiation complex of 30s. misreading mRNA. sever G- rods. ineffective against anaerobes. Nephro/ototoxicity
Aminoglycosides: gentamicin, neomycin, amikacin, tobramycin, streptomycin
binds 30s and inhibit tRNA binding. Borrelia, M. pneumonia, intracel (rickettsia and chlamydia)
Tetracyclines: doxycycline, minocycline
binds 23s rRNA in 50s, preventing translocation. atypical pneumonia, STDs, and G+ cocci
Macrolides: azithromycin, clarithromycin, erythromycin
Blocks peptidyltransferase at 50s. Meningitis and Rocky Mountain Spotted fever. cheap, devo countries
Chloamphenicol
Block translocation at 50s. anaerobes above the diaphragm (RT). SE: C diff.
Clindamycin
Para-aminobenzoic acid (PABA) antimetabolite, blocks dihydropteroate synthetase. Inhibit folate synth.
Sulfonamides: sulfamethoxazole (SMX), sulfisoxazole, sulfadiazine
inhibits dihydrofolate reductase. block folate synth. UTI. tough on bone marrow.
Trimethoprim (TMP)
inhibit DNA gyrase (topoisomerase II) and topoisomerase IV. not w/anat-acids. G- rods in GI and GU.
Flouroquinolones: Ciprofloxacin and other -floxacins
free radical formation. Anaerobes below diaphragm, protozoa, H. pylori. disulfiram-like rxn w/alcohol
Metronidazol
decrease synth of mycolic acid. solo prophylaxis of TB. Neurotoxic and Hepatotoxic
Isoniazid
inhibit DNA-dependant RNA-polymerase. TB, leprosy. P-450 inducer, orange body fluids
Rifampin, rifabutin.
mechanism unsure. acdify intracellular environment. Treat TB.
Pyrazinamide
block arabinosyltransferase, inhibit carbohydrate cell wall polymerization of TB. red-green color blind.
Ethambutol
