What?

Naloxone is an opioid antagonist used to reverse the effect of opioid intoxication.

Indicative in patients with reduced GCS or respiratory rate less than 10 breaths per minute as a result of known or likely opioid use.

For reversal in over 12 years olds:

Give 400 μg IV initially.

Then up to 2 doses of 800 μg.

After 1 min, then 2 mg if no response.

Care should be taken in opioid-dependent patients, it is best to start with smaller doses.

For reversal in children less than 12 years old:

Give 10 μg/kg IV (maximum per dose 2 mg).

Repeat every 1 minute to a total dose of 2 mg.

Why?

Following reversal of opioids, patients need to be observed for at least 6 hours longer with sustained-release preparations.

It is important to calculate the total dose required to maintain adequate ventilation for at least 15 minutes, as this is the patient's rescue or resuscitative dose.

If during this period they become intoxicated again it will be necessary to start a naloxone infusion. Patients who have had long-acting opioids usually require a naloxone infusion.

Set the initial rate at 60% of the initial rescue dose (to be given over one hour) increasing as required.

TOXBASE recommends 10 mg naloxone in 50mls of 0.9% NaCl or 5% Glucose (to a concentration 200 μg/ml).