METRONIDAZOLE

Question 1

Drug class

Answer 1

anaerobic antimicrobial

Question 2

How does it work? (6)

Answer 2

• works on anaerobic bacteria
• enters bacterial cells via diffusion
• metronidazole is reduced to nitrous free radical
• this free radical binds to DNA
• this reduces synthesis
• and causes cell death

Question 3

Indications and give examples of them (5)

Answer 3

1. antibiotic associated colitis
   - c.diff
2. oral infections
3. aspiration pneumonia
4. surgical and gynaecological infections

• gram -ve anaerobes
  5. protozoal infections

Question 4

Conta-indications (2)

Answer 4

1. severe liver disease - cytochrome P450 enzymes

2. alcohol

Question 5

Side effects (5)

Answer 5

1. GI upset - nausea and vomitting
2. hypersensitivity reactions
3. neuropathy - peripheral and optic
4. encephalopathy
5. seizures

Question 6

Interactions (give examples) (3)

Answer 6

1. cytochrome P450 enzymes - warfarin and phenytoin
2. cytochrome P450 inducers
3. Lithium - increases toxicity

Question 7

Eliminations

Answer 7

mainly urine

some faeces