Naloxone (Narcan): Reversing an Opioid Overdose
Naloxone can reverse an opioid overdose in minutes, if you are ready. Learn the signs, how to give it and what to expect, and keep it where you and the people around you can find it.
Think someone is overdosing? Call 911 first.
Then give naloxone and stay with them. Naloxone is safe to give even if you are not sure it is an opioid overdose.
Recognize it
Signs of an opioid overdose
- Won't wake up, or won't respond to your voice or touch
- Slow, shallow or stopped breathing
- Gurgling, choking or snoring sounds
- Blue or gray lips or fingertips
- Very small (pinpoint) pupils
- Limp body, pale or clammy skin
In an emergency
How to give naloxone nasal spray
- 1Call 911, or have someone else call while you help.
- 2Lay the person on their back and tilt their head back.
- 3Put the nozzle in one nostril and press the plunger to give the full spray. Narcan is a single spray of 4 mg into one nostril; other brands follow the strength on their label.
- 4If the person does not respond within 2 to 3 minutes, give a second dose into the other nostril with a new spray.
- 5If they start breathing, roll them onto their side (the recovery position) so they don't choke. If they are not breathing normally and you are trained, give rescue breaths or CPR.
- 6Stay with them until help arrives. Naloxone wears off in 30 to 90 minutes, and the overdose can come back.
Forms of naloxone
Naloxone doses by form
The right dose depends on the form of naloxone and how severe the overdose is. Too little might not reverse the overdose; too much can cause intense withdrawal in someone who is dependent on opioids.
Nasal spray (Narcan, Kloxxado)
The most common form for use at home and in the community. Narcan is a single spray of 4 mg into one nostril. If the person does not respond within 2 to 3 minutes, give a second dose into the other nostril. Kloxxado is a nasal spray with a higher dose of naloxone, useful when strong opioids like fentanyl are involved. Always give the full spray and follow the strength on the device's label. Nasal sprays are designed to be easy to use, even without medical training.
Injectable naloxone
Generic injectable naloxone is used by medical professionals and in some emergency kits. The typical first dose is 0.4 mg to 2 mg, given into a muscle, under the skin or into a vein. If there is no response, it can be repeated every 2 to 3 minutes until the person responds or emergency medical services take over. In severe cases, especially with strong opioids like fentanyl, higher doses or a continuous infusion may be needed.
Zimhi is a single-use prefilled syringe: give the full contents, following its label and the training you received.
Some overdoses, especially with very strong or long-acting opioids, need more than one dose. Watch the person closely after the first dose.
The basics
What naloxone is and how it works
Naloxone is an opioid antagonist: it blocks the effects of opioids. In an overdose, opioids such as heroin or fentanyl attach to receptors in the brain that control breathing, and breathing slows or stops. Naloxone attaches to the same receptors and pushes the opioids off, so the person can start breathing again and wake up.
It starts working within 2 to 5 minutes and lasts 30 to 90 minutes. Because some opioids last longer than that, the person still needs emergency care after naloxone.
Narcan is a brand name for one naloxone nasal spray. Other forms include Kloxxado nasal spray, Zimhi prefilled injection and generic naloxone.
Afterward
What to expect after giving naloxone
Naloxone reverses opioids quickly, so a person who depends on opioids may go into withdrawal. This is uncomfortable but usually not life-threatening, and it is a small price for reversing an overdose.
Common reactions
Nausea and vomiting, a fast heartbeat, sweating or fever, body aches, and feeling restless, anxious or irritable.
Rare but serious: get emergency care
Signs of an allergic reaction (hives, trouble breathing, swelling of the face, lips or throat), severe withdrawal (intense agitation, seizures, a sharp rise in blood pressure), or seizures in a newborn exposed to opioids before birth.
Be prepared
Who should keep naloxone close
Ask us about a naloxone prescription if you are in medication-assisted treatment, live with chronic pain, or share a household where someone could be accidentally exposed to opioids. Our providers will show you how to carry, store and use the nasal spray. Naloxone nasal spray is also sold over the counter at many pharmacies.
Storing naloxone
Keep it at room temperature, out of direct sunlight, and in its box until you need it. Tell the people around you where it is. Check the expiration date, and replace it when it expires or after you use it.
Naloxone is not a treatment for opioid addiction, but it is an important way to prevent a fatal overdose and give someone a second chance to seek treatment. If you or someone you love is ready for help, book an appointment.
Questions
Common questions
Can naloxone hurt someone who is not overdosing?
No. Naloxone has no effect on someone who does not have opioids in their system, so it is safe to give whenever you suspect an opioid overdose.
How quickly does naloxone work?
Naloxone can begin to work within 2 to 5 minutes, depending on how it is given. If the person does not respond within 2 to 3 minutes of a nasal spray dose, give a second dose in the other nostril.
How long does naloxone last?
Its effects last 30 to 90 minutes. Long-acting or very strong opioids, such as methadone or fentanyl, can outlast it, so the overdose can come back. Always call 911 and stay with the person.
Is Narcan the same as naloxone?
Narcan is a brand of naloxone nasal spray. All Narcan is naloxone, but not all naloxone is Narcan: there are other brands and forms, including Kloxxado nasal spray, Zimhi prefilled injection and generic naloxone.
In an emergency, call 911. For a mental health crisis, call or text 988 (Suicide & Crisis Lifeline).
You are not alone.
Questions about naloxone or opioid treatment? Our team is here to help.