Antibiotics
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  • DNA synth inh
    • Trimethoprim (TMP,): Tx: UTI. Mech: DHF analogue = inh DHFR = anti-THF = inh dTMP synth. SE: anti-folate (megalobastic anemia), for pts tx w PCP (rash, hepatitis). Fact: combine w sulfonamides (TMP/SMZ).
    • Sulfonamide (SMZ,): Tx: toxoplasmosis. Mech: PABA analogue = inh pteroate synthase = anti-folate = inh DNA synth. SE: blood dz (WBC↓, plt↓), kernicterus, rash, inh P450.
    • Fluoroquinolone: Tx: broad spec (pneumonia, UTI w pseudo aer, enteritis). Mech: inh DNA gyrase/topo II, topo IV. SE: tendon rupture, MRSA, C diff. Fact: the -floxacins.
    • Ciprofloxacin: Tx: broad spec (pneumonia, UTI w pseudo aer, enteritis). Mech: fluoroquinolone (inh gyrase/topo II, topo IV). SE: tendon rupture, avoid in kids, preg pts. Fact: not good for anaerobes.
    • Nalidixic acid: Tx: UTI. Mech: quinolone (inh gyrase/topo II).
    • Nitrofurantoin: Tx: UTI for preg pt. Mech: DNA dmg when reduced by bacteria.
  • Cell wall inh (b-lactam & friends)
    • Beta-lactam: Mech: D-Ala-D-Ala analogue = inh pen binding protein = inh peptidoglycan synth. Fact: the penicillins, cephalosporins, monobactams, carbapenems.
      • Penicillin: Tx: gram pos (Pen G,V), gram negs (newer -cillins). Mech: b-lactam. SE: if allergy (rash), then try aztreonam. Fact: the -cillins.
        • Penicillin G: Tx: gram pos (enterococci if add aminogly), syphilis. Mech: b-lactam. SE: if allergy (rash), then try aztreonam. Fact: penG (parenteral), penV (oral).
        • Penicillin V: Tx: gram pos (enterococci if add aminogly), syphilis. Mech: b-lactam. SE: if allergy (rash), then try aztreonam. Fact: penG (parenteral), penV (oral).
        • Ampicillin: Tx: UTI, otitis, gram pos. Mech: b-lactam.
        • Amoxicillin: Tx: otitis, sinusitis, pneumonia, UTI, gram pos. Mech: b-lactam. Fact: oral, combine w clavulanic acid for b-lactamase.
        • b-lactamase resistant
          • Methicillin: Tx: gram pos. Mech: b-lactamase resistant b-lactam.
          • Oxacillin: Tx: gram pos. Mech: b-lactamase resistant b-lactam.
          • Dicloxacillin: Tx: gram pos. Mech: b-lactamase resistant b-lactam.
        • gram negs
          • Ticarcillin (Timentin,): Tx: gram negs, pseudo aer. Mech: b-lactam. Fact: Timentin = ticarcillin + clavulanic acid.
          • Piperacillin: Tx: gram pos & negs, pseudo aer. Mech: b-lactam.
          • Mezlocillin: Tx: biliary inf, cholangitis, gram pos & negs, pseudo aer. Mech: b-lactam, liver excretion, good for biliary inf.
      • Cephalosporin: Tx: gram pos (1st gen), gram neg (2rd, 3rd gen), CNS (3rd gen). Mech: b-lactam. Fact: 1st gen (cephalexin), 2nd gen (cefuroxime), 3rd gen (ceftriaxone, cefotaxime).
        • 1st gen (gram pos)
          • Cephalexin: Tx: cellulitis, gram pos. Mech: b-lactam, 1st gen cephalosporin. Fact: oral.
          • Cephazolin: Tx: skin infections. Mech: b-lactam, 1st gen cephalosporin.
        • 2nd gen (some gram pos & negs)
          • Cefuroxime: Tx: gram pos & negs, H flu. Mech: b-lactam, 2nd gen cephalosporin.
          • Cefotetan: Tx: gram pos & negs. Mech: b-lactam, 2nd gen cephalosporin. SE: bleeding dz so co-Rx w Vit K.
        • 3rd gen (gram negs, CNS)
          • Ceftriaxone: Tx: meningitis, gram negs. Mech: b-lactam, 3rd gen cephalosporin.
          • Cefotaxime: Tx: meningitis, gram negs. Mech: b-lactam, 3rd gen cephalosporin.
          • Ceftazidime: Tx: gram negs, pseudo aer. Mech: b-lactam, 3rd gen cephalosporin.
      • Carbapenem: Tx: very broad spec. Mech: b-lactam. Fact: the -penems.
        • Imipenem: Tx: very broad spec, sepsis, gram pos & negs, pseudo aer. Mech: b-lactam.
        • Meropenem: Tx: very broad spec, meningitis. Mech: b-lactam.
    • Aztreonam: Tx: gram negs, pseudo aer. Mech: b-lactam (monobactam).
    • Clavulanic acid: Tx: combine w b-lactam. Mech: inh b-lactamase (covalent/suicidal).
    • Sulbactam: Tx: combine w b-lactam. Mech: inh b-lactamase.
    • Vancomycin: Tx: MRSA, C diff, gram pos. Mech: cassette binds D-Ala-D-Ala, too large for gram negs.
  • Protein synth inh
    • Aminoglycoside: Tx: gram negs (pos if add b-lactam), aerobes only. Mech: inh initiation complex, need O2 for uptake, bac-cidal. SE: nephrotox, ototox. Fact: don't cross CNS, inh by Ca, Mg, named -mycins (vs -thromycins for macrolids).
      • Streptomycin: Tx: gram negs (pos if add b-lactam), aerobes only. Mech: aminoglycoside (inh init). SE: ototox, nephrotox.
      • Neomycin (Neosporin,): Tx: hepatic encephalopathy (oral), skin infections (topical). Mech: aminoglycoside (inh init). SE: nephrotox (so not given IV), ototox.
      • Amikacin: Tx: gram negs, pseudo aer. Mech: aminoglycoside (inh init). SE: nephrotox, ototox. Fact: more resistant to inactivation.
      • Tobramycin: Tx: pseudo aer pneumonia. Mech: aminoglycoside (inh init). SE: nephrotox, ototox.
    • Macrolide: Tx: legionella, mycoplasma, chlamydia, whooping cough (bord pertussis). Mech: inh translocation. SE: antag w chloramphenicol, clindamycin, inh P450. Fact: the -thromycins.
      • Erythromycin: Tx: legionella, mycoplasma, chlamydia, whooping cough (bord pertussis). Mech: macrolid (inh translocation).
      • Clarithromycin: Tx: pharyngitis, sinusitis, tonsilitis. Mech: macrolid (inh translocation).
      • Azithromycin: Tx: otitis, strep throat. Mech: macrolid (inh translocation).
    • Tetracycline: Tx: RMSF (rickettsia), Q fever (coxiella). Mech: inh elongation (blk AA-tRNA binding). SE: phototox (rash), bone deposition (brown teeth, don't use for kids or preg pts), Fanconi (n/v, polyuria, proteinuria). Fact: inh by Ca, Mg, M3+.
      • Doxycycline: Tx: RMSF, Q fever, prostatitis, chlamydia. Mech: tetracycline (blk AA-tRNA binding, elongation). SE: phototox (rash), bone deposition (don't use for kids or preg pts), Fanconi (n/v, polyuria, proteinuria). Fact: fecal elim, so good for pt w renal dz.
    • Oxazolidinone: Tx: MRSA, VRE, gram pos superbugs. Mech: inh init. SE: plt↓, weak MAOI (avoid tyramine foods, other antidepressants), C diff. Fact: the -zolids.
      • Linezolid: Tx: MRSA, VRE, gram pos superbugs. Mech: oxazolidinone (inh init). SE: plt↓, act as MAOI (avoid tyramine foods, other antidepressants), C diff.
    • Chloramphenicol: Tx: meningitis, RMSF for kids & preg pts. Mech: inh peptidyl transferase. SE: aplastic anemia, marrow tox, gray baby.
    • Clindamycin: Tx: anaerobes (dental). Mech: inh elongation (blk AA-tRNA binding). SE: C diff. Fact: oral.
  • Metronidazole (Flagyl,): Tx: anaerobes, ameba, protozoa, parasites, C diff. Mech: dmg enzymes, DNA when reduced inside bugs. SE: carcinogen (don't give to preg pts).
  • Daptomycin: Tx: MRSA, VRSA, VRE, gram pos superbugs. Mech: lipopeptide (kill membrane potential). SE: myopathy (CK↑).