Antibacterials: Penicillins

Question 1

Penicillin G

Answer 1

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: IV; penicillinase-SENSITIVE; generally can pentrate all tissues besides eye, prostate and CNS ( but can enter CNS when meninges are inflammed (meningitis)
• clinical: SYPHILIS (Treponema pallidum), streptococci, meningococci, gram-positive bacilli, and spirochetes.
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• Misc: <1% of persons who previously had penicillin w/o incident will have an allergic reaction when given penicillin; can cause seizures in renal failure patients.

Question 2

Penicillin V

Answer 2

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: ORAL; penicillinase-SENSITIVE
• clinical: Oropharyngeal infections
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• misc: <1% of persons who previously had penicillin w/o incident will have an allergic reaction when given penicillin; can cause seizures in renal failure patients.

Question 3

Nafcillin

Answer 3

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: NOT oral (“erratic” in GI); Penicillinase-resistant
• clinical: For Staph infections that are methicillin-susceptible, B-lacatamase (penicillinase)-producing;
• toxicity/interactions: NEUTROPENIA; Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• misc: NEUTROPENIA

Question 4

Oxacillin

Answer 4

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Penicillinase-resistant (narrow spectrum)
• clinical: For Staph infections that are methicillin-susceptible, B-lacatamase (penicillinase)-producing
• toxicity/interactions: HEPATITIS; Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• misc: Can cause hepatitis

Question 5

Cloxacillin

Answer 5

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Penicillinase-resistant (narrow spectrum)
• clinical: S. aureus (not MRSA)
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins

Question 6

Dicloxacillin

Answer 6

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Penicillinase-resistant (narrow spectrum)
• clinical: S. aureus (not MRSA)
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins

Question 7

Ampicillin

Answer 7

-family: B-lactam/penicillin
-mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
-kinetics: Oral, Penicillinase-SENSITIVE
-clinical: Indicated infections for Penicillin G, but also for Enterococci, Listeria monocytogenes, E. coli, Proteus mirabilis, H. influenzae, and Moraxella catarrhalis
-toxicity/interactions: “MACULOPAPULAR RASH; nasuea, diarrhea, PSEUDOMEMBRANOUS COLITIS; Hypersensitivity reaction (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); complete cross-reactivity
with other penicillins”
-misc: MACULOPAPULAR RASH; Nausea and diarrhea OFTEN seen; implicated in pseudomembranous colitis; enhanced with penicillinase-inhibitors (eg. tazobactam, clavulanic acid); synergistic with aminoglycosides for listerial and enterococcal infections

Question 8

Amoxacillin

Answer 8

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Oral, Better oral bioavailability than ampicillin; Penicillinase-SENSITIVE
• clinical: Indicated infections for Penicillin G, but also for Enterococci, Listeria monocytogenes, E. coli, Proteus mirabilis, H. influenzae, and Moraxella catarrhalis
• toxicity/interactions: Can cause non-allergic skin rash, Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• misc: ONLY penicillin where absorption is NOT hindered by food–thus all other penicillins MUST be given 1-2 hrs before or after a meal; enhanced with penicillinase-inhibitors (eg. tazobactam, clavulanic acid)

Question 9

Ticarcillin

Answer 9

• family: B-lactam/penicillin
• Mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Penicillinase-SENSITIVE
• clinical: Pseudomonas aeruginosa; Gr-NEGATIVE rods: Pseudomonas, Enterobacter, and Klebsiella sp. (for some cases)
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• misc: Act synergistically with aminoglycosides; enhanced with penicillinase-inhibitors (eg. tazobactam, clavulanic acid)

Question 10

Azlocillin

Answer 10

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Penicillinase-SENSITIVE
• clinical: Pseudomonas
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins

Question 11

Pipericillin

Answer 11

• family: B-lactam/penicillin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall, stops cell wall synthesis, kills bacterium
• kinetics: Penicillinase-SENSITIVE
• clinical: Gr-NEGATIVE rods: Pseudomonas, Enterobacter, and Klebsiella sp. (for some cases)
• toxicity/interactions: Hypersensitivity reactions (urticaria, severe pruritus, fever, joint swelling, hemolytic anemia, nephritis, and anaphylaxis); nausea, diarrhea; complete cross-reactivity with other penicillins
• misc: Act synergistically with aminoglycosides; enhanced with penicillinase-inhibitors (eg. tazobactam, clavulanic acid)