Paracetamol

Question 1

when is paracetamol indicated? (2)

Answer 1

first line dental - mild to moderate dental pain
when NSAIDs contraindicated i.e. asthma, GI ulcers, reye’s syndrome, congenital/acquired coagulopathies

Question 2

list preparations that contain paracetamol

Answer 2

panadol
lemsip
beechams cold & flu
calpol
alvedon
solpadol
co-codamol

Question 3

what is paracetamol’s mode of action?

Answer 3

limited inhibition of COX 1 & 2

Question 4

peripheral or central action?

Answer 4

more peripheral

Question 5

when is it peak in plasma?

Answer 5

after 60 mins

Question 6

half life?

Answer 6

2-4hrs

Question 7

name the toxic by-product produced by paracetamol metabolism

Answer 7

NAPQI

Question 7

list contraindictaions of paracetamol - why are these contrainidctaed?

Answer 7

liver disease
alcohol
malnutrition
dehydration

may develop liver toxicity at lower plasma concentrations than the normal person

Question 7

what drugs does paracetamol interact with?

Answer 7

SCRAPPP

S - St johns wort
C - Carbamazepine
R - Rifampicin
P - Phenobarbital
P - Phenytoin
P - Primidone

Question 8

what is the max daily dose?

Answer 8

4g (8x 500mg tablets)

Question 9

how many tablets is the toxic dose?

Answer 9

20-30

Question 10

what is the standard dose? mg/kg

Answer 10

10-15mg/kg every 4-6hrs

Question 11

how many grams causes acute liver damage?

Answer 11

10-15g

Question 12

how many grams is fatal?

Answer 12

25g

Question 13

what can be given to tx overdose?

Answer 13

activated charcoal & acetylcysteine

Question 14

how will an overdose present within the first 24hrs? what is the % death rate?

Answer 14

nausea & vomiting
5% death rate