Antimicrobials Flashcards
Penicillin G & V
Natural penicillins (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Against gram positive. Bactericidal. G inactivated by gastric acid so can’t be taken orally. V less active by not inactivated by gastric acid. SE convulsions if given IV, <0.1% anaphylaxis
cefradine
1st gen cephalosporin (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Bactericidal. Highly active against gram+. Cross allergy w penicillin 5% of cases
Aztreonam
Monobactam (b lactam)
Notes - Bactericidal. Targets cell wall. Narrow spectrum -> Gram + bacilli, gram - aerobic, enterobacteria, pseudomonas. Used in penicillin & cephalosporin allergy.
Cefaclor
2nd gen cephalosporin (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Bactericidal. activity against gram -. Cross allergy w penicillin 5% of cases
Cefotaxime
3rd gen cephalosporin (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Bactericidal. Activity against gram+ (but less than 1st gen) & strong activity against gram- aerobes (more than 2nd gen) Cross allergy w penicillin 5% of cases
Cefepime
4th gen cephalosporin (b lactam)
Notes- Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Bactericidal. Highly resistant to beta-lactamase. Cross allergy w penicillin 5% of cases
Ceftaroline
5th gen cephalosporin (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Bactericidal. high activity against MRSA. Cross allergy w penicillin 5% of cases
Amoxicillin & ampicillin
Broad spectrum penicillins (b lactam)
Notes - Against Gram negative. Bactericidal. Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Amoxicillin oral, ampicillin lower bioavailability. SE convulsions if given IV, <0.1% anaphylaxis. Ampicillin given with sulbactam (b lactamase inhibitor)
Cloxacillin & floxacillin
b lactamase resistant penicillins (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. Only for methicillin SENSITIVE s. aureus (not MRSA) & some coliforms. Bactericidal. SE convulsions if given IV, <0.1% anaphylaxis
Carbenicillin & ticarcillin & ureidopenicillin
Extended spectrum carboxy-penicillins (b lactam)
Notes - Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. beta lactamase sensitive. Bactericidal. SE convulsions if given IV, <0.1% anaphylaxis
imipenem, meropenem, doripenem, ertapenem
carbapenems (b lactams)
Notes - Bactericidal. Target PBPs which are enzymes for cell wall synthesis which prevents NAG/NAM cross-linking peptide formation & activate autolysins. widest spectrum-> gram + cocci, gram - bacilli ex p. Aeruginosa. anaerobes
Vancomycin
Cell wall inhibitor (glycoprotein)
Notes - Bactericidal. drug of last resort when b lactams don’t work* On reserve for MRSA esp. S.aureus & C.diff* Forms bonds with D-Alanine in PG layer preventing incorporation of NAG/NAM. SE - RED MAN SYNDROME (rate dependent infusion reaction by activating mast cells to release histamine- not mediated by IgE), OTOTOXICITY, NEPHROTOXICITY
Teicoplanin
Cell wall inhibitor (glycoprotein)
Notes - Bactericidal. Longer half life (30h) than vancomycin (4-11h) & fewer S.E. Given IV or intramuscularly
Bacitracin
Cell wall inhibitor
Notes - bactericidal. Inhibits regeneration of lipid carrier of PG so can’t get to cell wall
Cycloserine
Cell wall inhibitor
Notes- Bactericidal. D-Alanine structural analogue so inhibits incorporation. Used for TB
Polymyxin B
Cell membrane inhibitor
Notes- Bactericidal. A detergent that displaces Mg & Ca in cell membrane making it leaky. Has high affinity for phospholipids TOPICAL USE ONLY for gram - (ex pseudomonas & coliforms) bc they have LPS layer which is exposed cell membrane