What is Naloxone?

Naloxone is a medicine that rapidly reverses an opioid overdose. It is an opioid antagonist. This means that it attaches to opioid receptors and reverses and blocks the effects of other opioids. Naloxone can quickly restore normal breathing to a person if their breathing has slowed or stopped because of an opioid overdose. But, naloxone has no effect on someone who does not have opioids in their system, and it is not a treatment for opioid use disorder. Examples of opioids include heroin, fentanyl, oxycodone (OxyContin®), hydrocodone (Vicodin®), codeine, and morphine.

What is Naloxone?

Naloxone is a medication approved by the Food and Drug Administration (FDA) to stop or reverse the effects of an overdose from opioids like heroin, morphine, and oxycodone. Naloxone blocks opioid receptor sites, reversing the toxic effects of an overdose.

Naloxone is administered when a patient shows signs of opioid overdose. The medication can be given by intranasal spray or by intramuscular (into the muscle), subcutaneous (under the skin), or intravenous injection.

Naloxone is also added to buprenorphine (brand name Suboxone) to decrease the chances of diversion and misuse of the medication.

What are some signs of an opioid overdose?

  • unconsciousness
  • very small pupils
  • slow or shallow breathing
  • vomiting
  • an inability to speak
  • faint heartbeat
  • limp arms and legs
  • pale skin
  • purple lips and fingernails

How is naloxone given?

Naloxone should be administered to anybody who shows symptoms of an opioid overdose or when an overdose is suspected. Naloxone can be administered through nasal spray or injection into the muscle, under the skin, or into the veins. Steps for responding to an opioid overdose can be found in the Substance Abuse and Mental Health Administration’s (SAMHSA) Opioid Overdose Prevention Toolkit .

What are the different naloxone delivery systems?

Naloxone comes in two FDA-approved forms: injectable and prepackaged nasal spray. No matter what dosage form you use, it’s important to receive training on how and when to use naloxone. You should also read the product instructions and check the expiration date.

  • Injectable brands of naloxone are offered by different companies listed in the FDA Orange Book under “naloxone” (look for “injectable”). The proper dose must be drawn up from a vial. Usually, it is injected with a needle into muscle, although it may also be administered into a vein or under the skin.

  • Prepackaged Nasal Spray (generic naloxone, Narcan®, Kloxxado®), developed as a result of NIDA-funded research , is an FDA-approved prefilled, needle-free device that requires no assembly and is sprayed into one nostril while the person lays on their back. This device can also be easier for loved ones and bystanders without formal training to use.

Can I give naloxone to someone who has overdosed?

Yes.Families who have loved ones who are addicted to opioids should keep naloxone on hand, ask a family member to carry it, and let others know where it is. In the event of an overdose, people should still dial 911 immediately.

Police officers, emergency medical technicians, and non-emergency first responders are using naloxone at a higher rate than in the past. In most places, persons who are at danger of an opioid overdose or know someone who is can be trained to administer naloxone.Families may learn how to use the devices by asking their pharmacists or health care providers.

What precautions are needed when giving naloxone?

Naloxone works to reverse opioid overdose in the body for only 30 to 90 minutes. But many opioids remain in the body longer than that. Because of this, it is possible for a person to still experience the effects of an overdose after a dose of naloxone wears off. Also, some opioids are stronger and might require multiple doses of naloxone. Therefore, one of the most important steps to take is to call 911 so the individual can receive immediate medical attention.

People who are given naloxone should be observed constantly until emergency care arrives. They should be monitored for another 2 hours after the last dose of naloxone is given to make sure breathing does not slow or stop.

People with physical dependence on opioids may have withdrawal symptoms within minutes after they are given naloxone. Withdrawal symptoms might include headaches, changes in blood pressure, rapid heart rate, sweating, nausea, vomiting, and tremors. While this is uncomfortable, it is usually not life threatening. The risk of death for someone overdosing on opioids is worse than the risk of having a bad reaction to naloxone. Clinicians in emergency room settings are being trained to offer patients immediate relief and referral to treatment for opioid use disorder with effective medications after an opioid overdose is reversed.

Side effects from naloxone are rare, but people might have allergic reactions to the medicine. Overall, naloxone is a safe medicine. But it only reverses an overdose in people with opioids in their systems and will not reverse overdoses from other drugs like cocaine or methamphetamine.

Side Effects of Naloxone

Patients who experience an allergic reaction from naloxone, such as hives or swelling in the face, lips, or throat, should seek medical help immediately. They should not drive or perform other potentially unsafe tasks.

Use of naloxone may cause symptoms of opioid withdrawal, including:
  • Feeling nervous, restless, or irritable

  • Body aches

  • Dizziness or weakness

  • Diarrhea, stomach pain, or nausea

  • Fever, chills, or goose bumps

  • Sneezing or runny nose in the absence of a cold

Points to remember

  • Naloxone is a medicine that rapidly reverses an opioid overdose. It attaches to opioid receptors and reverses and blocks the effects of other opioids.
  • Naloxone is a safe medicine. It only reverses overdoses in people with opioids in their systems.
  • There are two FDA-approved formulations of naloxone: injectable and prepackaged nasal spray.
  • Police officers, emergency medical technicians, and first responders are trained on how to give naloxone.
  • In some states, friends and family members can be trained on how to give naloxone.
  • Naloxone only works in the body for 30 to 90 minutes. It is possible for a person to still experience the effects of an overdose after naloxone wears off or need multiple doses if a potent opioid is in a person’s system.
  • In some areas, you can get naloxone from pharmacies with or without a personal prescription from community-based distribution programs, or local health departments. The cost varies depending on where and how you get it as well as what type you get.