Chemical Restraint


Chemical restraint or emergency sedation is used for management of acute behavioral emergencies.

  • A drug is considered a restraint when it is used as a restriction to manage the patient’s behavior or restrict the patient’s freedom of movement and is not a standard treatment or dosage for the patient’s condition.
  • The goal is to rapidly and safely sedate the patient to control symptoms and allow them to be safely managed without providing a threat to themselves or to staff
  • all available alternative treatment options should be considered before administering chemical or physical restraint, as it infringes an individual’s autonomy and dignity


  • actual or high risk of harm to self, others or property where verbal de-escalation is inappropriate or ineffective


  • medical instability
  • risk of harm to staff in applying restraint
  • alternative strategies available and appropriate


Ensure the following assessments are made before administering chemical restraint:

  • The patient is a serious threat to staff and/ or to themselves, (staff feel directly under threat)
  • The patient is unable to make rational decisions
  • Other less invasive options are inappropriate or ineffective (e.g. verbal de-escalation, involvement of trusted others)
  • The patient needs urgent medical assessment, intervention or treatment

Ensure that appropriate security staff and/ or police are always nearby during assessment to ensure staff safety

  • activate the appropriate code
  • safe physical restraint is often temporarily needed to safely administer chemical restraint

Investigations can be performed once the patient is stabilised (i.e. cooperative, physically restrained or sedated) – tests that are typically required include (others are performed on a case-by-case basis):

  • glucose
  • ethanol level
  • paracetamol level if suspected overdose


  • ECG (e.g. check for underlying long QT if antipsychotics used)


  • FBC
  • UEC
  • LFTs
  • septic screen if clinically indicate


  • CT brain (if suspected organic cause or traumatic brain injury) – may require intubation and sedation

Special tests

  • Urine drug screens do not affect initial management and are unnecessary; may be useful for documenting the possible cause for future reference


Exclude other therapeutic options first

  • e.g. attempt verbal de-escalation and involvement of trusted others

Prepare for chemical restraint

  • in emergency situations a psychiatry recommendation / Compulsory Treatment Order is not needed
  • assemble sufficient and appropriate security staff and/ or police members to physically restrain the patient (see physical restraint)
  • physiological monitoring is needed for any patient that receives IV sedatives

Consider factors that affect doses and dosing interval

  • level of agitation
  • response to treatment
  • body size
  • age
  • medical history
  • medication history (e.g. drug dependence)
  • previous response to sedative drugs

Choose route of drug administration

  • IM route is preferred if significant risk of harm to staff from attempting to obtain IV access
  • Take caution before giving additional doses if apparent failure to respond after IM administration (onset may be slow and erratic)
  • often initial sedation can be IV if appropriate physical restraint is performed
  • IV is more rapid, more predictable, more reliable, and easily titratable
  • subsequent sedation should be IV and titrated to effect

Choose agent and dose

  • benzodiazepines
    • lorazepam 1 to 2 mg PO/ SL / IV q2-6h, titrated to clinical response, up to a maximum of 10 mg in 24 hours
      • rapid onset
      • longer duration than midazolam
      • experts may consider administering higher doses in resistant patients
      • no CYP450 metabolism (undergoes conjugation), so compared to midazolam and diazepam:
        • no active metabolites
        • less affected by liver disease
        • less drug interactions
        • less individual variability
    • midazolam is a rapid, effective, short-acting sedative agent is an alternative
      • midazolam IM 5-10mg or IV 2.5-5mg q3min, titrated to response, up to 30mg (halve dose in the frail elderly)
      • ceiling doses of 30mg are typical (in tolerant patients >100mg may be needed; experts may give 10-20mg boluses in these cases)
      • midazolam is more likely to need repeat dosing than lorazepam due to shorter duration of action
    • diazepam 5 mg IV, q3min, titrated to response, up to 30 mg is an alternative
      • Diazepam has slower onset IV and is not recommended for IM injection as absorption is poor and erratic
    • Use benzodiazepines with caution in the elderly and patients with respiratory compromise
    • Droperidol or olanzapine should be considered in patients who are tolerant of benzodiazepines or if there is a failure of midazolam, effect is synergistic and patients may respond to low doses of antipsychotic (drugs should not be mixed in same syringe if given in combination)
  • typical antipsychotics e.g. haloperidol or droperidol
    • droperidol is more sedating
    • useful for controlling psychotic symptoms (e.g. delusions, hallucinations)
    • can be given IM or IV
    • associated with QT prolongation (risk is overstated, as is FDA’s black box warning for droperidol
    • Droperidol IM: 5 to 10 mg IM
    • Droperidol IV: 2.5 to 5 mg IV, q3min, titrated to response, up to 20mg
    • Haloperidol IM dose: 5 to 10 mg IM, up to 20mg in 24 hours.
    • Haloperidol IV titratable dose: Haloperidol 2.5 to 5 mg IV, repeated every 2 to 3 minutes, titrated to clinical response, up to 10 mg per sedation event. Halve these doses in the frail elderly patient
    • obtain ECG to monitor QT prolongation once sedated
  • atypical antipsychotics
    • in less extreme situations a longer acting IM dose may be appropriate
    • e.g. IM olanzepine 10mg
    • though not licensed for IV use in Australia, research supports the use of the IM formulation IV
    • e.g. olanzapine 5 mg IV, q5min, titrated to response, (maximum 20 mg IV)
    • IV onset similar to that of IV droperidol, but is longer acting
  • ketamine
    • an option in extreme situations, especially prehospital
    • e.g. ketamine 1mg/kg IV or 5 mg/kg IM
    • if patient remains non-sedated then give titrated midazolam in addition

Monitoring (according to depth of sedation) may include:

  • Pulse and respiratory rate
  • An initial temperature should be recorded
  • Pulse oximetry
  • ECG
  • Blood pressure
  • Close monitoring of conscious state and airway adequacy

Seek and treat complications

  • over-sedation (consider flumazenil to reverse benzodiazepines, but in dependent patients this may trigger withdrawal and/or seizures
  • complications of sedation and immobilisation
  • extra-pyramidal effects (consider IV benztropine)
  • physical injury to patient, staff or others


  • reason for restraint
  • alternative therapies attempted
  • assessment of potential injuries and any complications of restraint
  • monitoring plan
  • thresholds for further interventions
  • ongoing sedation options and sedation chart


  • once patient has stabilised and recovered from sedation explanation should be given
  • discuss strategies the patient can use to self-modulate behaviour in the future to prevent recurrences (if appropriate)
  • provide explanation and reassurance to the family


  • close observation will be necessary until the patient recovers from sedation (able to safely eat, drink and toilet)
  • psychiatric assessment

References and Links


Journal articles

  • Coburn VA, Mycyk MB. Physical and chemical restraints. Emerg Med Clin North Am. 2009 Nov;27(4):655-67, ix. PMID: 19932399.
  • Downes MA, Healy P, Page CB, Bryant JL, Isbister GK. Structured team approach to the agitated patient in the emergency department. Emerg Med Australas. 2009 Jun;21(3):196-202. PMID: 19527279.
  • Isbister GK, Calver LA, Page CB, Stokes B, Bryant JL, Downes MA. Randomized controlled trial of intramuscular droperidol versus midazolam for violence and acute behavioral disturbance: the DORM study. Ann Emerg Med. 2010 Oct;56(4):392-401.e1. PMID: 20868907.

FOAM and web resources

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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