Cephalosporins

Question 1

Cephalosporins - indications

Answer 1

Oral cephalosporins: second- and third-line options for Tx of urinary and respiratory tract infections.

Parenteral cephalosporins: very severe/complicated infections, or infections caused by antibiotic-resistant organisms.

Question 2

Cephalosporins - examples

Answer 2

cefalexin
cefotaxime
meropenem

Question 3

Cephalosporins - MOA

Answer 3

SAME AS PENICILLIN

1. inhibits the enzymes responsible for cross-linking peptidoglycans in bacterial cell walls.
2. weakens cell walls = uncontrolled entry of water into bacteria = cell swelling, lysis and death.

Question 4

Cephalosporins - adverse effects

Answer 4

1) Gastrointestinal (GI) upset, such as nausea and diarrhoea (COMMON)

2) antibiotic-associated colitis: can be complicated by colonic perforation and death.
(LESS COMMON)

3) Hypersensitivity, including immediate and delayed reactions - rashes, anaphylaxis
4) if high dose or given to renal patients- risk of neurological toxicity, including seizures

Question 5

Cephalosporins - should be avoided in patients with..

Answer 5

Hx of allergy to penicillin, cephalosporin or carbapenem - particularly if there was an anaphylactic reaction.

Question 6

Cephalosporins - used with caution in patients with..

Answer 6

1) at risk of C. difficile infection
2) epilepsy
3) renal impairment - dose reduction

Question 7

Cephalosporins - interactions

Answer 7

1) warfarin
2) aminoglycosides.
3) valproate.