Antibacterials: Cephalosporins

Question 1

Cephalexin

Answer 1

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: Oral
• clinical: Skin and soft tissue infections; UTI
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 1st generation

Question 2

Cefadroxil

Answer 2

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: oral
• clinical: Skin and soft tissue infections; UTI; surgical prophylaxis
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 1st generation; used as surgical prophylaxis

Question 3

Cefazolin

Answer 3

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: oral
• clinical: Skin and soft tissue infections; UTI; surgical prophylaxis
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 1st generation; used as surgical prophylaxis

Question 4

Cefuroxime

Answer 4

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: oral
• clinical: Pneumococcus and Haemophilus influenzae
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 2nd generation; better activity against gram positive

Question 5

Cefotetan

Answer 5

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: IV; disulfiram-like reaction (/w EtOH)
• clinical: Bacteroides fragilis (allows for use in abdominal/pelvic infections); Pneumococcus and Haemophilus influenzae
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 2nd generation; better activity against gram positive

Question 6

Cefaclor

Answer 6

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: oral
• clinical: Pneumococcus and Haemophilus influenzae
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 2nd generation; better activity against gram positive

Question 7

Cefoxitin

Answer 7

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: IV
• clinical: Bacteroides fragilis (allows for use in abdominal/pelvic infections); Pneumococcus and Haemophilus influenzae
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 2nd generation; better activity against gram positive

Question 8

Moxalactam

Answer 8

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: Enters CNS; IV
• clinical: Pneumonia, meningitis, pyelonephritis, and gonorrhea
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 3rd generation; better activity against gram-negative

Question 9

Cefotaxime

Answer 9

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: Enters CNS; IV; Shorter than regular half-life
• clinical: Pneumonia, meningitis, pyelonephritis, and gonorrhea
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 3rd generation; better activity against gram-negative

Question 10

Ceftriaxone

Answer 10

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: Enters CNS; IV; Longer than regular half-life
• clinical: Pneumonia, meningitis, pyelonephritis, and gonorrhea
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 3rd generation; better activity against gram-negative

Question 11

Ceftazidime

Answer 11

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: Enters CNS; IV
• clinical: Poor gram-positive activity; Pseudomona
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 3rd generation; better activity against gram-negative

Question 12

Cefepime

Answer 12

• family: B-lactam/cephalosporin
• mechanism: Binds to PBP (transpeptidase) and prevents cross-linking of peptidoglycan cell wall
• kinetics: Enters CNS; IV; Resistant to B-lactamases
• clinical: Broad activity against gram-negative; Pseudamonas
• toxicity/interactions: Hypersensitivity reaction; GI distress; complete cross-reactivity with cephalosporins, partial with penicillins
• misc: 4th generation; improved stability to B-lactamase!