Chloral Hydrate Poisoning

  • Statewide logo

    This guideline has been adapted for statewide use with the support of the Victorian Paediatric Clinical Network

  • See also

    Poisoning – Acute Guidelines for Initial Management
    Acute pain management 

    Key points

    1. Chloral hydrate is used safely for in-hospital sedation but it has been associated with deaths, particularly when used in the outpatient setting, usually in doses >10g,
    2. Chloral hydrate has a narrow therapeutic index. Recommended dose is 10-50 mg/kg up to 2g. Severe toxicity is seen at >100 mg/kg

    For 24 hour advice, contact Victorian Poisons Information Centre 13 11 26


    • Chloral hydrate is used primarily for sedation for radiological and dental procedures.
    • Toxicity is rapid onset (<30 min) with CNS depression and cardiac dysrhythmias.
    • It can be corrosive to mucosal surfaces in high doses


    • Absorption is rapid, but slower if fasting.
    • Peak serum concentration occurs in 30-60 mins.

    Dose related toxicity

    • Care should be taken with giving multiple doses over a short period of time.
    • No more than 100 mg/kg should be given per procedure
    • No more than 200 mg/kg should be given over a 24 hour period.
    • Doses higher than the above are associated with coma and cardiac dysrhythmias.
    • Acute overdose >10 g can cause gastric haemorrhage, perforation and strictures.

    Patients requiring assessment

    • All patients with deliberate self-poisoning or significant accidental ingestion
    • Any symptomatic patient
    • Dose >50 mg/kg

    Non-accidental poisoning should be considered in any patient whose developmental age is inconsistent with accidental poisoning,

    Risk Assessment


    • Intentional overdose or accidental
    • Dose:
      • Stated or likely dose taken
      • Calculate the maximum possible dose per kg
    • Consider co-ingestants
    • All adolescents who present with a deliberate self-poisoning should be assessed for ongoing mental health risk. 
      • Assessment should determine whether an adolescent needs: 
        • admission to an Adolescent Mental Health Ward for their safety, or
        • follow up support by a community based mental health service, and / or
        • linkage with a drug and alcohol support service


    • CNS depression: drowsiness and ataxia progressing rapidly to coma
    • Respiratory depression
    • Hypotension
    • Hypothermia
    • GI corrosive injury

    Always check for Medicalert bracelet in any unconscious patient, or any other signs of underlying medical condition (fingerprick marks etc)


    • ECG: Multifocal PVC, AF, SVT, VT
    • Consider endoscopy within 24 hours in ingestions >10g showing clinical signs of corrosive injury.
    • Paracetamol level in all intentional overdoses

    Acute Management


    • Standard procedures and supportive care
    • Early intubation if progressive CNS depression or CVS toxicity.
    • Dysrhythmias        
      • Beta blocker: esmolol or propranolol
    • Torsades
      • add MgSO4, though this may be ineffective
    •  VT
      • lignocaine may be effective
    • Hypotension –
      • IV fluids: 20 mL/kg 0.9% saline.
      • Catecholamine inotropes are contraindicated as they may precipitate arrhythmias


    • Charcoal contraindicated unless airway protected.

    Enhanced elimination

    • Haemodialysis – consider if ongoing haemodynamic instability or arrhythmias

    Consider consultation with local paediatric team when

    Contact Victorian Poisons Information Centre 13 11 26 for advice

    • Admission should be considered for all adolescent patients with an intentional overdose.
    • Adolescents who NEED hospital admission for medical treatment of their poisoning:
      • Adolescent must be assessed for ongoing risk of deliberate self harm on the ward before transfer to the ward to enable appropriate supervision and support.
      • However, this should not delay urgent care, such as ICU admission.
    • Adolescents who DO NOT NEED hospital admission for medical treatment of their poisoning
      • Liaise with your on-call hospital based Mental Health Service before discharge (if available)
      • Arrange ongoing support through a local mental health service: eg
        • Headspace National Youth Mental Health Foundation (12-25 years old), go to Headspace  and click “Find a centre”
      • Victorian Child and Adolescent Mental Health Services (CAMHS)  (0 – 18 years old), go to Mentalhealth Services and search by region based on residential address

     Consider transfer when

    Patients with CVS depression or CVS arrhythmias should be managed in a paediatric ICU.

    For emergency advice and paediatric or neonatal ICU transfers, call the Paediatric Infant Perinatal Emergency Retrieval (PIPER) Service: 1300 137 650.

    Discharge Criteria

    • All symptomatic patients should be observed until asymptomatic
    • Normal GCS
    • Normal ECG
    • Post at least 2 hours of cardiac monitoring
    • For deliberate ingestion a risk assessment should indicate that the patient is at low risk of further self-harm in the discharge setting

    Discharge information and follow-up


    Last Updated August 2018