Intravenous Paracetamol : Emergency Learning

1 Intravenous (IV) paracetamol should be prescribed carefully, according to the weight, age and co-morbidities
of the patient. The upper dose limit for each single dose and in each 24-hour period should not be exceeded.
2 50ml vials of IV paracetamol should be used for patients less than 33kg. In infants and small children, doses
should be measured accurately using a syringe.
3 Enquiry about recent paracetamol ingestion should form part of routine pre-operative assessment. All doses
of paracetamol administered in the operating theatre should be recorded on the ward drug administration
chart and in the anaesthetic record.
4 Advice should be sought from the local poisons information service in all cases of overdose of intravenous
paracetamol. Treatment with acetylcysteine is suggested following a single dose greater than 60mg/kg.
5 Intravenous paracetamol (Perfalgan®) remains under intensive monitoring by the MHRA. All suspected
adverse reactions to IV paracetamol should be reported to the Yellow Card Scheme and discussed with the
local poisons information service.

 Background
A Fatal Accident Inquiry in Scotland in 2011 concluded that a young adult died from liver failure due to an overdose
of paracetamol. The Sheriff found ‘there was, at the time of the death, a prevailing culture of assumed familiarity with
the administration of IV paracetamol, a familiarity derived from the common use of oral paracetamol’. The patient,
who weighed 35kg, died nine days after receiving paracetamol 1g IV on a sustained and regular basis.1
Intravenous paracetamol was licensed in the UK in 2004 and is used routinely in anaesthetic practice. Since
introduction, there have been concerns about accidental overdose of IV paracetamol due to errors in drug prescription
and administration, particularly in children, small adults, the elderly, alcoholics and those with pre-existing
hepatocellular insufficiency.
Reported errors include incorrect dose in adults with high or low body mass index; accidental overdose in children
associated with use of 100ml-vials; 10-fold drug calculation errors; confusion between dose volume in millilitres and
dose of drug in milligrams; errors when setting up infusion pumps; and duplication of doses between the ward and
the operating theatre or recovery.2-5
Examples of recent reports to the NRLS include:
➤ Patient had a dose of paracetamol before going to theatre and then was given another dose whilst in theatre. Fifth
dose in 24 hours.
➤ Paracetamol not given on the ward post op due to double dose given in theatre...
➤ Patient was given the prescribed 1gram paracetamol on the ward at 08:13hrs as part of pre-med. On return to ward
after procedure it was noted on the anaesthetic chart that 1gram of IV paracetamol had been given at 09:30 hrs...
The MHRA issued a Patient Safety Update in 2010 that raised concerns about accidental overdose of IV paracetamol
(Perfalgan®), especially in infants and neonates. Perfalgan® is presented in a concentration of 10mg/ml, and in
most cases, a 10-fold overdose was reported. The MHRA advised vigilance when prescribing and administering
Perfalgan®, to adhere to recommended doses and dose intervals, to avoid concomitant administration by different
routes, and to use 50ml vials for infants and children who weighed less than 33kg.3
The NPSA issued a Signal alert in 2010 that raised concern about the risk of inadvertent overdose of IV paracetamol
in children, and described 206 incidents relating to IV paracetamol, two associated with severe harm and 14 with
moderate harm.5

recoMMended dose of iv paracetaMol
The dose of IV paracetamol recommended by the MHRA for children and adults is shown in the table below.
Paracetamol should be given by infusion over 15 minutes, and the minimum dose interval should not be less than four
hours (six hours in patients with renal impairment).

*The dose of IV paracetamol is controversial in neonates and infants. The BNF for Children (BNFC) suggests a dose of
7.5mg/kg every 8 hours (maximum 25mg/kg daily) in preterm neonates over 32 weeks postmenstrual age, 10mg/kg
every 4-6 hours (maximum 30mg/kg daily) in neonates.6
**The British National Formulary (BNF) suggests caution in patients with hepatocellular insufficiency, chronic
alcoholism, chronic malnutrition or dehydration, and to administer a maximum daily infusion dose of 3g in adults in
these patient groups.