Contributor: Taylor Lynch, MD
Educational Pearls:
Opioid Epidemic- quick facts
Drug overdoses, primarily driven by opioids, have become the leading cause of accidental death in the U.S. for individuals aged 18-45.
In 2021, opioids were involved in nearly 75% of all drug overdose deaths
The rise of synthetic opioids like fentanyl, which is much more potent than heroin or prescription opioids, has played a major role in the increase in overdose deaths
What is Narcan AKA Naloxone?
Competitive opioid antagonist. It sits on the receptor but doesn't activate it.
When do we give Narcan?
Respiratory rate less than 8-10 breaths per minute
Should you check the pupils?
An opioid overdose classically presents with pinpoint pupils BUT…
Hypercapnia from bradypnea can normalize the pupils
Taking other drugs at the same time like cocaine or meth can counteract the pupillary effects
Basilar stroke could also cause small pupils, so don't anchor on an opioid overdose
How does Narcan affect the body?
Relatively safe even if the patient is not experiencing an opioid overdose. So when in doubt, give the Narcan.
What if the patient is opioid naive and overdosing?
Use a large dose given that this patient is unlikely to withdraw
0.4-2 mg every 3-5 minutes
What if the patient is a chronic opioid user
Use a smaller dose such as 0.04-0.4 mg to avoid precipitated withdrawal
How fast does Narcan work?
Given intravenously (IV), onset is 1-2 min
Given intranasal (IN), onset is 3-4 min
Given intramuscularly (IM), onset is ~6 min
Duration of action is 60 mins, with a range of 20-90 minutes
How does that compare to the duration of action of common opioids?
Heroine lasts 60 min
Fentanyl lasts 30-60 min, depending on route
Carfentanyl lasts ~5 hrs
Methadone lasts 12-24 hrs
So we really need to be conscious about redosing
How do you monitor someone treated with Narcan?
Pay close attention to the end-tidal CO2 to ensure that are ventilating appropriately
Be cautious with giving O2 as it might mask hypoventilation
Watch the respiratory rate
Give Narcan as needed
Observe for at least 2-4 hours after the last Narcan dose
Larger the dose, longer the observation period
Who gets a drip?
If they have gotten ~3 doses, time to start the drip
Start at 2/3rds last effective wake-up dose
Complications
Flash pulm edema
0.2-3.6% complication rate
Might be from the catecholamine surge from abrupt wake-up
Might also be from large inspiratory effort against a partially closed glottis which creates too much negative pressure
Treat with BIPAP if awake and intubation if not awake
Should you give Narcan in cardiac arrest?
Short answer no. During ACLS you take over breathing for the patient and that is pretty much the only way that Narcan can help
Just focus on high quality CPR
References
Elkattawy, S., Alyacoub, R., Ejikeme, C., Noori, M. A. M., & Remolina, C. (2021). Naloxone induced pulmonary edema. Journal of community hospital internal medicine perspectives, 11(1), 139–142. https://doi.org/10.1080/20009666.2020.1854417
van Lemmen, M., Florian, J., Li, Z., van Velzen, M., van Dorp, E., Niesters, M., Sarton, E., Olofsen, E., van der Schrier, R., Strauss, D. G., & Dahan, A. (2023). Opioid Overdose: Limitations in Naloxone Reversal of Respiratory Depression and Prevention of Cardiac Arrest. Anesthesiology, 139(3), 342–353. https://doi.org/10.1097/ALN.0000000000004622
Yousefifard, M., Vazirizadeh-Mahabadi, M. H., Neishaboori, A. M., Alavi, S. N. R., Amiri, M., Baratloo, A., & Saberian, P. (2019). Intranasal versus Intramuscular/Intravenous Naloxone for Pre-hospital Opioid Overdose: A Systematic Review and Meta-analysis. Advanced journal of emergency medicine, 4(2), e27. https://doi.org/10.22114/ajem.v0i0.279
Summarized by Jeffrey Olson MS2 | Edited by Meg Joyce & Jorge Chalit, OMSII