Paracetamol overdose

Question 1

What level of paracetamol ingestion counts as an overdose?

Answer 1

Over 75mg/kg

Question 2

Paracetamol overdose makes up 50% of all ______ _____ _______ in the UK

Answer 2

fulminant liver failure

Question 3

What are symptoms of a paracetamol overdose?

Answer 3

Acute severe RUQ pain
Severe N+V

Question 4

Normally, most paracetamol undergoes what kind of conjugation to be excreted?

Answer 4

Phase II conjugation (gluconidation)

Question 5

Usually only a small amount of paracetamol undergoes phase I conjugation by _______ proteins to produce a toxic substance

Answer 5

CYP450

Question 6

What is the toxic product of Phase I conjugation of paracetamol by CYP450?

Answer 6

NAPQI

Question 7

Normally, any toxic NAPQI undergoes phase II conjugation with g_____ to form metabolites which are excreted

Answer 7

glutathione

Question 8

In a paracetamol overdose, the phase II conjugation pathway is saturated leading to more _____ _ _________ by CYP450 proteins

Answer 8

phase I conjugation

Question 9

In a paracetamol overdose, there is increased phase I conjugation and soon the supply of g_____ becomes depleted

Answer 9

glutathione

Question 10

During paracetamol overdose, what does depletion of glutathione result in?

Answer 10

Accumulation of toxic NAPQI in liver

Question 11

What is treatment for a paracetamol overdose?

Answer 11

Activated charcoal (within 1 hour of paracetamol ingestion)
+
N-Acetyl-cysteine (NAC)

Question 12

How does N-Acetyl-Cysteine (NAC) help a paracetamol overdose?

Answer 12

Increases availability of glutathione to get rid of excess NAPQI