3.5 Paracetamol toxicity
ANTIDOTES AND CHELATORS
Acetylcysteine 03-Apr-2018
lINDICATIONS AND DOSE
Paracetamol overdosage
▶BY INTRAVENOUS INFUSION
▶Neonate:Initially 150 mg/kg over 1 hour, dose to be
administered in 3 mL/kg glucose 5 %, followed by
50 mg/kg over 4 hours, dose to be administered in
7 mL/kg glucose 5 %, then 100 mg/kg over 16 hours, dose
to be administered in 14 mL/kg glucose 5 %.▶Child (body-weight up to 20 kg):Initially 150 mg/kg over
1 hour, dose to be administered in 3 mL/kg glucose 5 %,
followed by 50 mg/kg over 4 hours, dose to be
administered in 7 mL/kg glucose 5 %, then 100 mg/kg
over 16 hours, dose to be administered in 14 mL/kg
glucose 5 %
▶Child (body-weight 20–39 kg):Initially 150 mg/kg over
1 hour, dose to be administered in 100 mL glucose 5 %,
followed by 50 mg/kg over 4 hours, dose to be
administered in 250 mL glucose 5 %, then 100 mg/kg
over 16 hours, dose to be administered in 500 mL
glucose 5 %
▶Child (body-weight 40 kg and above): 150 mg/kg over
1 hour, dose to be administered in 200 mL Glucose
Intravenous Infusion 5 %, then 50 mg/kg over 4 hours,
to be started immediately after completion offirst
infusion, dose to be administered in 500 mL Glucose
Intravenous Infusion 5 %, then 100 mg/kg over
16 hours, to be started immediately after completion of
second infusion, dose to be administered in 1 litre
Glucose Intravenous Infusion 5 %
Meconium ileus
▶BY MOUTH
▶Neonate: 200 – 400 mg up to 3 times a day if required.Treatment of distal intestinal obstructive syndrome
▶BY MOUTH
▶Child 1 month–1 year: 0. 4 – 3 g as a single dose
▶Child 2–6 years: 2 – 3 g as a single dose
▶Child 7–17 years: 4 – 6 g as a single dose
Prevention of distal intestinal obstruction syndrome
▶BY MOUTH
▶Child 1 month–1 year: 100 – 200 mg 3 times a day
▶Child 2–11 years: 200 mg 3 times a day
▶Child 12–17 years: 200 – 400 mg 3 times a day
DOSESATEXTREMESOFBODY-WEIGHT
▶To avoid excessive dosage in obese patients, a ceiling
weight of 110 kg should be used when calculating the
dose for paracetamol overdosage.lUNLICENSED USENot licensed for use in meconium ileus
or for distal intestinal obstructive syndrome in children
with cysticfibrosis.
IMPORTANT SAFETY INFORMATION
MHRA/CHM ADVICE: INTRAVENOUS ACETYLCYSTEINE FOR
PARACETAMOL OVERDOSE: REMINDER OF AUTHORISED DOSE
REGIMEN; POSSIBLE NEED FOR CONTINUED TREATMENT
(JANUARY 2017)
The authorised dose regimen for acetylcysteine in
paracetamol overdose is 3 consecutive intravenous
infusions given over a total of 21 hours.
Continued treatment (given at the dose and rate as
used in the third infusion) may be necessary depending
on the clinical evaluation of the individual patient.lCAUTIONS
▶With intravenous useAsthma (see Side-effects for
management of asthma but do not delay acetylcysteine
treatment).atopy.may slightly increase INR.may slightly
increase prothrombin time
▶With oral useAsthma.history of peptic ulceration
lSIDE-EFFECTS
▶With parenteral useAcidosis.anaphylactoid reaction.
angioedema.anxiety.arrhythmias.cardiac arrest.chest
discomfort.cough.cyanosis.eye pain.eye swelling.
generalised seizure.hyperhidrosis.hypertension.
hypotension.joint disorders.malaise.nausea.pain facial
.respiratory disorders.skin reactions.syncope.
thrombocytopenia.vasodilation.vision blurred.vomiting
SIDE-EFFECTS, FURTHER INFORMATIONAnaphylactoid
reactions (with intravenous use) can be managed by
suspending treatment and initiating appropriate
management. Treatment may then be restarted at lower
rate.
lDIRECTIONS FOR ADMINISTRATION
▶With oral useFororaladministration, use oral granules,or
dilute injection solution ( 200 mg/mL) to a concentration of
50 mg/mL; orange or blackcurrant juice or cola drink may
be used as a diluent to mask the bitter taste.
▶With intravenous useGlucose 5 % is preferredfluid; Sodium
Chloride 0. 9 % is an alternative if Glucose 5 % unsuitable.lMEDICINAL FORMS
There can be variation in the licensing of different medicines
containing the same drug. Forms available from special-order
manufacturers include: effervescent tablet, granules
Granules
CAUTIONARY AND ADVISORY LABELS 13
▶A-CYS(Ennogen Healthcare Ltd)
Acetylcysteine 200 mgA-CYS 200 mg granules sachets| 20 sachet
£ 75. 00
Solution for infusion
ELECTROLYTES:May contain Sodium
▶Acetylcysteine (Non-proprietary)
Acetylcysteine 200 mg per 1 mlAcetylcysteine 2 g/ 10 ml solution for
infusion ampoules| 10 ampouleP£ 21. 26 – £ 24. 99 DT = £ 21. 26
▶Parvolex(Phoenix Labs Ltd)
Acetylcysteine 200 mg per 1 mlParvolex 2 g/ 10 ml concentrate for
solution for infusion ampoules| 10 ampouleP£ 22. 50 DT =
£ 21. 264 Methaemoglobinaemia
ANTIDOTES AND CHELATORS
Methylthioninium chloride
(Methylene blue)
lINDICATIONS AND DOSE
Drug- or chemical-induced methaemoglobinaemia
▶BY SLOW INTRAVENOUS INJECTION
▶Neonate:Seek advice from National Poisons Information
Service.▶Child 1–2 months:Seek advice from National Poisons
Information Service
▶Child 3 months–17 years:Initially 1 – 2 mg/kg, then
1 – 2 mg/kg after 30 – 60 minutes if required, to be given
over 5 minutes, seek advice from National Poisons
Information Service if further repeat doses are
required; maximum 7 mg/kg per course
Aniline- or dapsone-induced methaemoglobinaemia
▶BY SLOW INTRAVENOUS INJECTION
▶Child 3 months–17 years:Initially 1 – 2 mg/kg, then
1 – 2 mg/kg after 30 – 60 minutes if required, continued→BNFC 2018 – 2019 Methaemoglobinaemia 843
Emergency treatment of poisoning16