Narcan (Naloxone) for Reversing Opioid Overdose

Written by Jonathan Strum

& Medically Reviewed by Benjamin Caleb Williams, RN

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Last Updated - 10/28/2022

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Updated 10/28/2022

Narcan is a life-saving medication that instantaneously reverses an opioid overdose. This effect is only temporary, though, so emergency treatment is still necessary.

Narcan (naloxone) is a medication that can save a person’s life during an opioid overdose. Narcan temporarily reverses the effects of an opioid overdose, allowing the person who is overdosing to get emergency treatment before it is too late.

Overdose rates have been rising, and over 80,000 opioid-related deaths occurred in 2021 alone. These statistics illustrate the importance of overdose reversal medications like Narcan. If someone you love is struggling with opioid addiction, it’s important to be aware of overdose risks and understand how to reverse an overdose using Narcan.

About Opioid Overdose

An opioid overdose can occur when someone uses too high of an opioid dose or combines opioids with other substances that cause similar effects. Opioids interact with opioid receptors in the brain and slow down nerve signals. At low doses, this merely inhibits pain and causes tiredness. However, at higher doses, this can suppress or even stop someone’s breathing.

Opioid overdoses often occur in people who have an opioid addiction. Addiction frequently leads someone to overuse substances, often impulsively or when judgment is impaired. Over 10 million people misuse opioids each year, and many are at risk of developing an addiction or experiencing an overdose.

What Is Narcan?

Narcan is an opioid reversal agent that instantly reverses the effects of opioids and completely stops an opioid overdose. Narcan is designed to be used in emergency situations to temporarily reverse an overdose and provide the person the time they need to get to a hospital.

Narcan Forms

Narcan comes in three different forms. Two are available for emergency use by everyday people, and one is available for use by health care professionals. The forms of Narcan include:

  • Nasal spray: Designed to be sprayed directly into a nostril, this form of Narcan is easy to administer and absorbs quickly.
  • Auto-injector: This form of Narcan is a single-use injector that automatically activates during use. An auto-injector injects Narcan into muscle or fat tissue.
  • Injectable: This form of Narcan typically comes in a vial and must be used and prepared by a health care professional. This form is often used in hospitals and is given slowly and continuously through an IV.

Narcan for Opioid Overdose Reversal

While many medications have multiple uses, Narcan’s only role is to reverse the effects of an opioid overdose. Narcan is the only medication currently approved for this purpose, and it is used because it acts very quickly.

Because Narcan only works for reversing opioids, health care professionals will sometimes administer it to patients they suspect of overdosing on opioids. This is done to see if it causes any effects, and it helps determine if the patient is overdosing on opioids or not.

How Does Narcan Work?

Narcan works by attaching to the same receptors as opioids, but unlike opioids, it does not activate these receptors. When Narcan is present, the opioid receptors are not able to be stimulated by opioids. This completely reverses the effects that opioids have. However, Narcan is metabolized by the body much faster than opioids. This means that the effects of opioids will outlast Narcan, causing overdose symptoms to eventually return.

How Long Does Narcan Stay in Your System?

Narcan wears off very quickly. Importantly, it does not last as long as opioids, meaning that the effects of an opioid overdose can return as Narcan wears off. Narcan will last for about 30 to 90 minutes; however, in severe cases, the duration of Narcan could be even shorter.

How To Administer Narcan

The correct way to administer Narcan varies based on the form that it comes in and the way it is manufactured. When administering Narcan, you should always follow the instructions that come with it.

For nasal Narcan:

  1. Remove any cover over the nozzle.
  2. Insert the nozzle into an unobstructed nostril.
  3. Press the plunger or activate the nasal spray device.

For auto-injectable Narcan:

  1. Remove any cover over the tip.
  2. Press the tip firmly against the side of the thigh, pressing against clothing if necessary.
  3. Hold the tip against the thigh for three to five seconds, then remove it.

Colorado’s Third Party Naloxone Law

Colorado’s Third Party Naloxone law is a law that specifically states that anyone — even if they are not a health care provider — can administer Narcan in Colorado if they suspect a person is suffering an opioid overdose. This law protects a person who uses Narcan on someone who may be having an opioid overdose, and it encourages people to provide life-saving care without fear of legal repercussions.

Narcan Training Resources

There are many different resources that teach people how to use Narcan and how to respond during an overdose. Some options include:

  • Reputable emergency response organizations: Organizations like the Red Cross provide courses and education that may be in-person or online.
  • State and local governments: Many state and local governments, such as the City of Philadelphia, provide free resources and training related to Narcan.
  • Local health care businesses: Your local hospital or clinics may offer Narcan training and could be a valuable resource.

What Happens if You Give Narcan to Someone Who Doesn’t Need It?

Giving Narcan to someone who does not need it rarely has any negative effects. In some very unusual situations, an individual could be allergic to Narcan or have a very rare side effect, but the odds of this occurring are very low.

Because there are almost always no negative effects from Narcan, most medical experts recommend giving Narcan to anyone who could potentially be overdosing on opioids. The benefits of giving Naran to someone who is overdosing are huge, and there is almost no downside to giving it to someone who is not actually overdosing.

Narcan Side Effects

Narcan itself has almost no meaningful side effects. While some people have reported dizziness or nausea when using it, it rarely creates any side effects itself. However, Narcan does cause almost instantaneous opioid withdrawal. This is not a side effect of Narcan; rather, it is the main effect that Narcan is intended to cause.

The symptoms of instantaneous opioid withdrawal can be very unpleasant and may include:

  • Agitation
  • Pain
  • Achiness
  • Nausea
  • Vomiting
  • Diarrhea
  • Stuffy nose
  • Tearing
  • Irritability

Opioids are typically used to treat pain or abused to cause a high. Using Narcan will instantly reverse any and all pain-killing effects and completely end a high. This often causes the person receiving Narcan to suddenly become very agitated.

How To Get Narcan in Colorado

Getting Narcan requires a prescription. However, in Colorado, the state’s chief medical officer has created a standing order that allows anyone in Colorado to receive Narcan without a prescription. While this is technically different from making Narcan an over-the-counter medication, it essentially makes it accessible to everyone. Anyone in Colorado should be able to purchase Narcan from a pharmacy without having to see a provider first.

How Much Does Narcan Cost?

Narcan is the brand name for the generic medicine naloxone. The brand name does nothing to change the medicine, and generic naloxone works exactly the same as Narcan. Like most medications, the brand name does change the price significantly, even though there is no difference between the generic and brand-name medication. In Colorado, Narcan nasal spray costs $130 to $140 for a two-dose kit, while the same medicine without the brand name costs $20 to $40.

Free Narcan

The availability of free Narcan is constantly changing, but the city of Denver is providing free Narcan to residents of the city. Other local governments in Colorado may or may not have similar programs in place. You should check with your local government to see if free Narcan is available in your area.

The Importance of Medical Attention After Narcan

It is absolutely essential for people to go to the hospital after receiving Narcan. While Narcan will reverse the effects of a life-threatening overdose within a minute or two, it will wear off before the opioids do, and the overdose will reoccur.

Narcan is packaged in single doses. Often, when an overdose reoccurs after Narcan is given, there is no more Narcan available, and the overdose is more likely to be fatal. Because Narcan only temporarily reverses the overdose, it is essential to still seek medical help.

Will You Be Arrested After Receiving Treatment for an Overdose?

While laws vary by state, most states have laws protecting people who overdose or report an overdose from any legal actions related to seeking medical attention. It is important to note that these laws only cover overdose situations. If you are reporting an overdose and volunteer information about other episodes of drug use, the information is unlikely to be protected.

In Colorado, someone reporting an overdose is immune from prosecution for drug-related charges if the charges arise from reporting the overdose. This only applies if the people involved cooperate with the police and medical professionals and stay with the overdose victim until help arrives.

Getting Help for Opioid Addiction in Colorado

No one ever plans to have a fatal opioid overdose, yet tens of thousands of people die from overdoses each year. If you or a loved one is struggling with an opioid addiction, the best way to avoid the risks of an overdose is to stop using opioids. This can be difficult to do alone, but professional opioid rehab treatment can help.

The Recovery Village at Palmer Lake offers some of the best opioid addiction care available in Colorado. Our state-of-the-art facility and caring staff can help you achieve the results you are looking for. Contact us today to learn more about how we can help you address your opioid addiction and begin a healthier, drug-free life in recovery.


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