Reversing An Opioid Overdose With Narcan (Naloxone)

A person experiencing an opioid overdose needs immediate medical attention. Call 911 immediately and let them know the person is unresponsive and not breathing. This article references people affected by opioid misuse, overdose death, and other substance-related problems. If you don’t suspect an overdose but are in distress, please find a crisis hotline here

According to the Centers for Disease Control and Prevention (CDC), in 2021, over 80,000 opioid-involved overdose deaths happened in the United States.¹

An estimated 40% occurred with a bystander present, who, with the right resources, might have been able to intervene.²

Naloxone, also known by its brand name Narcan, is a life-saving medication used for the emergency treatment of an opioid overdose. 

It belongs to a class of drugs called opioid receptor antagonists. Biochemically, it means Narcan counteracts the effects of opioids by binding with their receptors, making them unavailable to opioid action. (It is not a treatment for opioid misuse or addiction).³

Narcan’s active ingredient, naloxone hydrochloride, was first approved by the US Food and Drug Administration (FDA) in 1971.⁴

For decades, paramedics and emergency care teams have successfully given injectable Narcan to reverse opioid overdoses.

However, for years its use stayed mainly within emergency medical response situations. Whereas today, in the US, it is an easy-to-use spray, accessible at a nearby store or gas station.⁵

In 2015, the FDA approved an intranasal (nasal spray) form of Narcan for the first time. At that point, it required a prescription.⁶

Then, in March 2023, prepackaged nasal Narcan was prioritized and approved in the US for over-the-counter use without a prescription.⁷

Today it is widely available at US grocery stores, pharmacies, and online, and it’s become a vital tool for confronting the opioid overdose epidemic and saving lives.

Here’s what you need to know about getting Narcan to someone in need.

Which drugs are opioids?

Numerous drugs, including some prescription medications, are opioids.⁸

For example:

  • Fentanyl 

  • Heroin

  • Oxycodone 

  • Oxymorphone

  • Hydrocodone 

  • Buprenorphine

  • Codeine

  • Morphine

  • Carfentanil (10,000 times more potent than morphine and 100 times stronger than fentanyl)⁹

The American Society of Anesthesiologists reports that over 2 million Americans misuse opioids.¹⁰

(Common brand names for prescription opioids include OxyContin, Palladone, Percocet, Vicodin, Actiq, Duragesic, and Sublimaze).

In addition, the circulation of fentanyl and carfentanil-laced drugs — cocaine, crack (smokable cocaine), heroin, methamphetamines, ketamine, and MDMA (ecstasy), and sometimes other substances — increases accidental opioid overdoses.¹¹ ¹²

What are the signs of an opioid overdose?

Signs of opioid poisoning (toxicity) include¹³ ¹⁴

  • Tiny “pinpoint” pupils

  • Confusion

  • Cold, damp skin

  • Extreme drowsiness

  • Limp body

  • Awake but unable to speak 

  • Gurgling or choking noises (often mistaken for snoring)

  • Loss of consciousness (you cannot wake the person, even by shouting at them) 

  • Fingertips, toes, or lips are discolored (if the person’s skin is dark, their extremities may look white or gray, or, in a light-skinned person, it may have a blue or dark purple hue)

  • Shallow, irregular breathing, or not breathing at all 

  • Slow, weak, or no pulse at all

Call 911 immediately if you suspect someone is experiencing an overdose. 

If you’re unsure, treating the situation as an overdose is best — you might save a life.

What does Narcan do?

Narcan is used to counter the effects of opioids rapidly. It temporarily “bumps” opioid molecules off their receptors in the central nervous system, negating their life-threatening effects and restoring suppressed breathing.¹⁵

If you take immediate action, Narcan can partially or fully restore breathing, reduce sedation, and save a person's life within about two to three minutes.¹⁶

However, it’s not a substitute for emergency medical care. Always call 911 after administering Narcan. There are various reasons why medical attention may be necessary, even if the overdose gets reversed. 

For instance, Narcan’s effects are temporary (typically 20–90 minutes), and additional doses may be required. Also, treating an opioid-dependent person with Narcan can cause acute opioid withdrawal (common symptoms include agitation, nausea, vomiting, and increased blood pressure).¹⁷

Narcan is not an antidote for all types of drug overdoses. It negates the effects of opioids. It won’t do anything if you give Narcan to someone who doesn’t need it.¹⁸

Even if you are unsure which drugs have been taken (or whether they could also contain fentanyl or other opioids), giving Narcan as a precaution will not cause harm or side effects. Instead, giving someone Narcan who doesn't need it does nothing. So, the biggest risk is not giving Narcan when it’s necessary.¹⁹

Unfortunately, you cannot give yourself Narcan. However, you can keep it on you and let someone know you’re carrying it. It must be administered by someone with you.²⁰

How do you give Narcan? 

You don’t need special medical training to give Narcan. It comes in various forms, including a pre-filled nasal spray (the most common, easy-to-use format). 

It comes in a pack of two containing 

  • 4mg of naloxone per spray

  • Disposable gloves

  • Detailed instructions

Read the step-by-step instructions in your kit when you get it. Check that it is not expired or about to reach the expiry date (stamped on the device). Do not test the device or depress the plunger before using it (it is ready to go).

If you are about to administer Narcan to someone, follow the instructions in the kit. They will be the most current.

However, here are some steps you can expect to take if you eventually give Narcan²¹

  1. First, recognize the overdose signs (the person is unresponsive even after you shout, breathing is slow/stopped, or their pupils are tiny).

  2. Call 911 for help (or ask someone nearby to call).

  3. Tell the person, “I am going to give you Narcan.” 

  4. Carefully lie them on their back.

  5. Remove Narcan from its case or package.

  6. Put on the throwaway gloves that come with the kit.

  7. Place your hand under the person’s neck and gently tilt their head back.

  8. Hold the spray with your thumb on the plunger and your fingers on both sides of the nozzle.

  9. Insert the spray nozzle into one nostril.

  10. Firmly push the plunger to dispense the Narcan dose into their nose.

  11. Remove the nozzle from that nostril.

  12. Place the person in a recovery position on their side.

  13. Wait two to three minutes—if they are still unconscious or not breathing better, give another dose (switching to the other nostril).

  14. If you know how to give rescue breathing, perform it until emergency medical help arrives. 

Do’s and Don’ts

The Substance Abuse and Mental Health Administration (SAMHSA) urges these guidelines:²²

  • DO keep Narcan readily accessible, especially where individuals at risk of opioid overdose live.

  • DO tell your friends and family where Narcan is kept.

  • DO help the overdose victim get oxygen by giving breaths (CPR) if you know how.

  • DO give another Narcan dose if they do not respond to the first.

  • DO stay by the person and wait for help (don’t leave them alone).

  • DO place them in a recovery position on their side.

  • DO keep them warm.

  • DON’T use force (such as slapping) to rouse someone who is overdosing. They may be unconscious if you have tried shouting, lightly pinching them or rubbing your knuckles in the center of their chest (sternum), and they still are unresponsive.

  • DON’T bring the person into a cold bath or the shower (despite possibly having seen this on TV or in movies). Doing so increases the odds of them going into shock, falling, or drowning.

  • DON’T try to induce vomiting up swallowed drugs (this can result in fatal choking or inhalation of vomit).

The lowdown

Narcan (naloxone) is a critical tool for opioid overdose prevention. It is no longer technology for emergency professionals only. Having it handy throughout communities saves lives. In recent years it has become increasingly available in the US. Since it does not require a prescription, anybody can carry Narcan now. Nasal-spray Narcan is easy to give and does not require giving an injection. If you suspect an overdose and give Narcan, but the person doesn’t have opioids in their system (they didn’t need it), it won’t harm them. The greater risk is not giving Narcan to someone when needed.

The information provided is designed to support, not replace, the relationship between a patient/site visitor and their existing health care professional(s). Have feedback? Email

  1. Drug Overdose Death Rates | National Institute on Drug Abuse (NIDA)

  2. Overdose Deaths and the Involvement of Illicit Drugs | Feature Topics

  3. Narcan (naloxone nasal spray) Approved to Reverse Opioid Overdose | FDA

  4. Naloxone facts and formulations |

  5. (As above)

  6. FDA moves quickly to approve easy-to-use nasal spray to treat opioid overdose | U.S. Food and Drug Administration

  7. FDA Approves First Over-the-Counter Naloxone Nasal Spray. | U.S. Food and Drug Administration

  8. Opioids | National Institute on Drug Abuse (NIDA).

  9. Carfentanil | C24H30N2O3 | CID 62156 - PubChem

  10. What Are Opioids? - Opioid Definition | Made for This Moment

  11. Carfentanil and the Rise and Fall of Overdose Deaths in the United States | PMC

  12. Cocaine and ketamine in Sydney and New South Wales found laced with life-threatening opioids | Daily Mail Online

  13. Opioid overdose |

  14. Recognizing Opioid Overdose | National Harm Reduction Coalition

  15. Understanding Naloxone | National Harm Reduction Coalition

  16. Frequently Asked Questions about Naloxone | Centers for Disease Control and Prevention

  17. Understanding Naloxone | National Harm Reduction Coalition

  18. Access to Naloxone Can Save a Life During an Opioid Overdose | FDA

  19. Naloxone DrugFacts | National Institute on Drug Abuse (NIDA)

  20. Frequently Asked Questions about Naloxone | Centers for Disease Control and Prevention

  21. Lifesaving Naloxone | Centers for Disease Control and Prevention

  22. SAMHSA Opioid Overdose Prevention Toolkit | Store SAMHSA

Cynthia is a Vancouver-based medical writer and editor who explores LGBTQIA+ health, neurodiversity, and addiction recovery.

Have you considered clinical trials for your medical condition?

We make it easy for you to participate in a clinical trial for your medical condition, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

Discover which clinical trials you are eligible for

Do you want to know if there are any a medical condition clinical trials you might be eligible for?
Have you taken medication for a medical condition?
Have you been diagnosed with a medical condition?