to be given over 5 minutes, seek advice from National
Poisons Information Service if further repeat doses are
required; maximum 4 mg/kg per courselCAUTIONSChildren under 3 months (more susceptible to
methaemoglobinaemia from high doses of
methylthioninium).chlorate poisoning (reduces efficacy
of methylthioninium).G6PD deficiency (seek advice from
National Poisons Information Service).
methaemoglobinaemia due to treatment of cyanide
poisoning with sodium nitrite (seek advice from National
Poisons Information Service).pulse oximetry may give
false estimation of oxygen saturation
lINTERACTIONS→Appendix 1 : methylthioninium chloride
lSIDE-EFFECTS
▶Common or very commonAbdominal pain.anxiety.chest
pain.dizziness.headache.hyperhidrosis.nausea.pain in
extremity.paraesthesia.skin reactions.taste altered.
urine discolouration.vomiting
▶Frequency not knownAphasia.arrhythmias.confusion.
faeces discoloured.fever.haemolytic anaemia.
hyperbilirubinaemia (in infants).hypertension.
hypotension.mydriasis.tremor
lPREGNANCYNo information available, but risk to fetus of
untreated methaemoglobinaemia likely to be significantly
higher than risk of treatment.
lBREAST FEEDINGManufacturer advises avoid
breastfeeding for up to 6 days after administration—no
information available.
lRENAL IMPAIRMENT
Dose adjustmentsUse with caution in severe impairment;
dose reduction may be required.
lDIRECTIONS FOR ADMINISTRATIONForintravenous
injection, may be diluted with Glucose 5 % to minimise
injection-site pain; not compatible with Sodium Chloride
0. 9 %.lMEDICINAL FORMS
There can be variation in the licensing of different medicines
containing the same drug. Forms available from special-order
manufacturers include: solution for injection
Solution for injection
▶Methylthioninium chloride (Non-proprietary)
Methylthioninium chloride 5 mg per 1 mlMethylthioninium
chloride Proveblue 50 mg/ 10 ml solution for injection ampoules|
5 ampouleP£ 196. 895 Snake bites
IMMUNE SERA AND IMMUNOGLOBULINS›
ANTITOXINSEuropean viper snake venom
antiserum
lINDICATIONS AND DOSE
Systemic envenoming from snake bites|Marked local
envenoming
▶BY INTRAVENOUS INJECTION, OR BY INTRAVENOUS INFUSION
▶Child:Initially 10 mL for 1 dose, then 10 mL after
1 – 2 hours if required, the second dose should only be
given if symptoms of systemic envenoming persist
after thefirst dose, if symptoms of systemic
envenoming persist contact the National Poisons
Information ServiceSevere systemic envenoming from snake bites in patients
presenting with clinical features
▶BY INTRAVENOUS INJECTION, OR BY INTRAVENOUS INFUSION
▶Child:Initially 20 mL for 1 dose, if symptoms of
systemic envenoming persist contact the National
Poisons Information ServicelDIRECTIONS FOR ADMINISTRATIONByintravenous injection
given over 10 – 15 minutes or byintravenous infusionover
30 minutes after diluting in sodium chloride 0. 9 %(use
5 mL diluent/kg body-weight).
lPRESCRIBING AND DISPENSING INFORMATIONTo order,
email [email protected].lMEDICINAL FORMS
There can be variation in the licensing of different medicines
containing the same drug.
Solution for injection
▶European viper snake venom antiserum (Non-proprietary)
European viper snake venom antiserum 100 mg per 1 mlViper
venom antiserum, European (equine) 1 g/ 10 ml solution for injection
vials| 1 vialPs844 Snake bites BNFC 2018 – 2019
Emergency treatment of poisoning16