gastro intestinal acetylcysteine

Question 1

3 indications for acetylcysteine

Answer 1

• antidote paracetamol poisoning
• prevent renal injury, contrast nephropathy
• reduce viscosity respiratory secretions (mucolytic)

Question 2

mechanism of action of acetylcysteine in paracetamol overdose

Answer 2

• patacetamol metabolism> conjugation> NAPQI is hepatotoxic
  -usually detoxified by conjugation with glutathione but in paracetamol poisoning - glutathione pathway saturated so NAPQI freely causes liver damage
• aceetylcysteine replenishes the body’s supply of glutathione

Question 3

mechanism of action of acetylcysteine in paracetamol overdose

Answer 3

• patacetamol metabolism> conjugation> NAPQI is hepatotoxic
  -usually detoxified by conjugation with glutathione but in paracetamol poisoning - glutathione pathway saturated so NAPQI freely causes liver damage
• aceetylcysteine replenishes the body’s supply of glutathione

Question 4

important adverse effect of acetylcysteine

Answer 4

anaphylactoid reaction
- nausea, tachycardia, rash, wheeze
- give antihistamine and bronchodilator

Question 5

when is it most effective to administer acetylcysteine in paracetamol poisoning

Answer 5

within 8 hours of a single overdose

Question 6

monitoring for paracetamol poisoning and administration of acetylcysteine

Answer 6

• INR
  -ALT activity
  -creatinine concentration