Effectiveness and safety of large bolus intramuscular naloxone for opioid poisoning in the Emergency Department

Effectiveness and safety of large bolus intramuscular naloxone for opioid poisoning in the Emergency Department: A randomised controlled trial

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12621000062820

Enrollment

136

Registered

2021-01-25

Start date

2021-10-14

Completion date

2023-10-18

Last updated

2025-09-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This study aims to find the best dose and route for naloxone to safely reverse the respiratory depression of opioid poisoning. This is a randomised controlled trial where adult patients with opioid poisoning and respiratory depression will receive a 100mcg intravenous bolus of naloxone and either a 1600mcg intramuscular bolus of naloxone or saline placebo. Patients will then be managed along the standard opioid poisoning pathway (where they are closely observed and receive titrated 100mcg IV boluses 5 minutely as required to reverse respiratory depression). We anticipate that the patients receiving the 1600mcg intramuscular bolus will have less recurrence of opioid toxicity and less requirement for a naloxone infusion without having an increased rate of opioid withdrawal symptoms.

Interventions

Patients in the treatment arm will receive a 100mcg bolus of intravenous naloxone and a single 1600mcg bolus of naloxone via the intramuscular route. Patients will then be managed along the standard opioid poisoning pathway where they are closely observed and receive 100mcg naloxone IV 5 minutely as required to reverse respiratory depression (defined as a respiratory rate >9 and oxygen saturations >92% on room air) until they are discharged from the Emergency Department.

Study design

Allocation

Randomised controlled trial

Intervention model

Parallel

Primary purpose

Treatment

Masking

Blinded (masking used) (Subject, Caregiver, Outcomes Assessor)

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

Adult patients > 17 years old presenting to the Princess Alexandra Hospital Emergency Department that require naloxone to reverse respiratory depression (defined as a respiratory rate < 10 or oxygen saturations < 93%) due to suspected opioid poisoning

Exclusion criteria

• Patients in which intravenous access is unable to be obtained • Patients who have iatrogenic poisoning following opioid administration for acute pain • Patients who are intubated and ventilated for management of concurrent conditions such as aspiration pneumonitis or to facilitate management of co-ingestions agents. • Patients in police or corrections custody

Outcome results