Also you should remember this..
+Sulfonamides compete for albumin with:
- Bilirrubin: given in 2°,3°T, high risk or indirect hyperBb and kernicterus in premies
- Warfarin: increases toxicity: bleeding
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* Beta-lactamase (penicinillase) Suceptible:
- Natural Penicillins (G, V, F, K)
- Aminopenicillins (Amoxicillin, Ampicillin)
- Antipseudomonal Penicillins (Ticarcillin, Piperacillin)
* Beta-lactamase (penicinillase) Resistant:
- Oxacillin, Nafcillin, Dicloxacillin
- 3°G, 4°G Cephalosporins
- Carbapenems
- Monobactams
- Beta-lactamase inhibitors
* Penicillins enhanced with:
- Clavulanic acid & Sulbactam (both are suicide inhibitors, they inhibit beta-lactamase)
- Aminoglycosides (against enterococcus and psedomonas)
* Aminoglycosides enhanced with Aztreonam
* Penicillins: renal clearance EXCEPT Oxacillin & Nafcillin (bile)
* Cephalosporines: renal clearance EXCEPT Cefoperazone & Cefrtriaxone (bile)
* Both inhibited by Probenecid during tubular secretion.
* 2°G Cephalosporines: none cross BBB except Cefuroxime
* 3°G Cephalosporines: all cross BBB except Cefoperazone bc is highly highly lipid soluble, so is protein bound in plasma, therefore it doesn’t cross BBB.
* Cephalosporines are “LAME“ bc they do not cover this organisms
- L isteria monocytogenes
- A typicals (Mycoplasma, Chlamydia)
- M RSA (except Ceftaroline, 5°G)
- E nterococci
* Disulfiram-like effect: Cefotetan & Cefoperazone (mnemonic)
* Cefoperanzone: all the exceptions!!!
- All 3°G cephalosporins cross the BBB except Cefoperazone.
- All cephalosporins are renal cleared, except Cefoperazone.
- Disulfiram-like effect
* Against Pseudomonas:
- 3°G Cef taz idime (taz taz taz taz)
- 4°G Cefepime, Cefpirome (not available in the USA)
- Antipseudomonal penicillins
- Aminoglycosides (synergy with beta-lactams)
- Aztreonam (pseudomonal sepsis)
* Covers MRSA: Ceftaroline (rhymes w/ Caroline, Caroline the 5°G Ceph), Vancomycin, Daptomycin, Linezolid, Tigecycline.
* Covers VRSA: Linezolid, Dalfopristin/Quinupristin
* Aminoglycosides: decrease release of ACh in synapse and act as a Neuromuscular blocker, this is why it enhances effects of muscle relaxants.
* DEMECLOCYCLINE: tetracycline that’s not used as an AB, it is used as tx of SIADH to cause Nephrogenic Diabetes Insipidus (inhibits the V2 receptor in collecting ducts)
* Phototoxicity: Q ue S T ion?
- Q uinolones
- Sulfonamides
- T etracyclines
* p450 inhibitors: Cloramphenicol, Macrolides (except Azithromycin), Sulfonamides
* Macrolides SE: Motilin stimulation, QT prolongation, reversible deafness, eosinophilia, cholestatic hepatitis
* Bactericidal: beta-lactams (penicillins, cephalosporins, monobactams, carbapenems), aminoglycosides, fluorquinolones, metronidazole.
* Baceriostatic: tetracyclins, streptogramins, chloramphenicol, lincosamides, oxazolidonones, macrolides, sulfonamides, DHFR inhibitors.
* Pseudomembranous colitis: Ampicillin, Amoxicillin, Clindamycin, Lincomycin.
* QT prolongation: macrolides, sometimes fluoroquinolones
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