Home Articles Other Medical Concerns Naloxone in EMS: Narcan Administration for Opioid Overdose

Naloxone in EMS: Narcan Administration for Opioid Overdose

It is 3 am on a summer overnight shift and you and your partner are called to treat a male patient in his mid-20s who is not breathing and has no pulse. When you arrive, you find the local fire department on scene with the male patient, who is lying supine on the floor while fire personnel provide chest compressions and manual ventilation with a bag-valve-mask device.

They have already placed a nasal pharyngeal airway (NPA) and administered 4mg of naloxone prior to your arrival. There was no change with manual ventilation or naloxone administration. You quickly place your 12-lead monitor and analyze the patient’s heart rhythm. The patient is in a slow pulseless electrical activity (PEA) rhythm. You initiate an IV and administer 1mg of epinephrine while you continue chest compressions and manual ventilation. One of the firefighters tells you that they found a needle in the patient’s leg and they suspect an opioid overdose. He asks you if you want to push more Narcan. You say no, and he seems upset but continues per your directions. So, who is right?

Over the last decade, the use of naloxone, also known as Narcan, in the pre-hospital setting has become more prevalent. Opioid abuse has increased and the “cutting” or adding of fentanyl or carfentanil has progressively spiked in recent years. First responders are finding patients in respiratory arrest or in full cardiac arrest.

When patients who have overdosed on opioids are found quickly enough and administration of Narcan is given early, the patient can many times be revived with zero neurologic deficits.

Learn more about opioid prevention and Narcan administration in our EMS course library.

Naloxone, Carfentanil, and Fentanyl

Naloxone, known to the general public as Narcan, is an opioid-reversal agent. It works by non-selectively and competitively binding to opioid receptor sites in the brain, thus reversing the potent effects of opioids, such as depressed respiratory function and apnea. Naloxone has a quick distribution throughout the body and half-life is generally around 30 minutes to an hour and a half. Redosing of Narcan may be necessary since many opioid substances have a longer duration of action. Heroin, one of the most commonly abused opioids used by narcotic addicts, is easy to obtain and cheap to buy.

Heroin is also sometimes mixed with other drugs to produce a deeper feeling of analgesia or “high,” drugs such as fentanyl or the more dangerous carfentanil. Carfentanil like fentanyl is much more potent than morphine. Carfentanil is 10,000 times more potent than morphine and generally requires multiple doses of Narcan to revive or reverse its effects. Unlike heroin, carfentanil is synthetic, meaning it is man-made and is not naturally occurring. The cost of both fentanyl and carfentanil is much cheaper than pure heroin. Therefore, dealers are “cutting” their heroin with these substances in order to make more money.

Carfentanil was originally designed for analgesia of large mammals, such as elephants, but in recent years has found its way into the illegal drug world. This new adoption of carfentanil exposes first responders to the very serious risk of overdose themselves. The smallest amount, less than the size of a penny, in contact with the skin can cause overdose. First responders should remain vigilant whenever a white powder is present on scene.

Narcan Administration

The use of naloxone is indicated in any person who is unresponsive and thought to be or known to be experiencing opioid overdose. If opioid overdose is not known but is possible, naloxone administration is still indicated. Indications include respiratory depression or apnea, altered mental status or unresponsiveness, constricted pupils, and drug paraphernalia present on scene. Narcan can be administered intravenously (IV), intraosseously (IO), intranasally (IN), intramuscularly (IM), or down the endotracheal tube (ETT). IV administration is preferred, but any route can result in a favorable outcome.

Dosing can range from 0.04mg to 4mg. An initial dose of 0.04mg IV or IO with repeated doses up to 2mg is the usual dosing for the advanced life support (ALS) pre-hospital provider. Dosing when given IV or IO usually takes effect within 1-2 minutes. If unable to initiate IV or IO access, the ALS provider can consider delivery through the ETT, but with the increased use and availability of IO/IN administration, the use of ETT has drastically decreased in recent years.

BLS providers may initiate 2mg IN or IM, and some BLS providers, such as fire personnel, may carry a 4mg naloxone IN single-dose injector.

Due to the high rate of opioid overdose in the community, the release of community-delivered Narcan kits have become much more readily available and are often used prior to first responder arrival. These kits generally include 2-4mg of naloxone and a nasal mucosal atomizer, which makes the Narcan a mist that can be easily and quickly absorbed through the mucosal membrane and delivered to the bloodstream. Intramuscular administration requires a needle and syringe to deliver the Narcan into a large muscle group.

The usual starting dose for IM administration is 2mg. Both IN and IM administration take up to 5 minutes for results. Delivery through ETT may take even longer. The max dose is 10 mg; however, with fentanyl or carfentanil present, a dose exceeding 10mg may be necessary. Dosing should be given in 5-minute intervals.

Airway and Cardiac Considerations

Patient receiving advanced life support after opioid overdose

The deadly side effect of opioid overdose usually results from a depressed respiratory rate or apnea leading to hypoxia, respiratory arrest, and further cardiac arrest if the patient is not quickly treated. The patient requires oxygen delivery quickly and effectively. This can be done in several different ways. If the patient is found and no medical personnel is available, a by-stander can administer mouth-to-mouth resuscitation. Once first responders arrive, the first thing they will do is confirm the patient still has a pulse. If no pulse is found, normal advanced life support care is initiated with the start of defibrillation pads added to the patient’s chest and analyzing of the patient’s cardiac rhythm. If a shockable rhythm is detected, then defibrillation should be given. Currently, there is debate about whether Narcan at this point should be indicated. The American Heart Association’s (AHA) stance is that there is no benefit in giving the patient Narcan, as the primary reason the patient is in full cardiac arrest is due to hypoxia. By providing manual ventilation with a bag-valve-mask device (BVM), the hypoxia is reversed, and the patient will turn around if significant brain damage has not already occurred. If the patient has gone without oxygen for too long, they generally will not survive or they will have an anoxic brain injury and will be neurologically compromised.

Patient care should focus on airway and ventilation and then quickly responding to the cardiac rhythm with appropriate advanced life support. The administration of Narcan should not delay cardiac rhythm analyzation and defibrillation. The advanced provider should be cautious of advanced airway placement and administration of naloxone. A patient that presents in respiratory arrest or cardiac arrest with naloxone administration and an advanced airway in place may respond to the naloxone administration within several minutes and risks becoming alert and oriented and pulling the advanced airway, risking traumatic injury to the vocal cords. While this risk is low, it could result in severe airway compromise due to trauma. Advanced providers should consider airway, breathing, and ventilation with a basic airway adjunct, such as a nasal pharyngeal airway (NPA) or oral pharyngeal airway (OPA) and BVM ventilation with high-flow oxygen.

If, after several minutes of resuscitation and Narcan administration, the patient has not improved in his or her respiratory and cardiac status, then the advanced provider may consider advanced airway placement with either a supraglottic airway device such as a King airway or I-gel or the gold standard of placement of an endotracheal tube. Both SPO2 saturation and ETCO2 with continuous waveform capnography should be monitored regardless of the airway chosen. If the patient begins to spontaneously breathe at an appropriate rate and depth, the airway adjunct can be removed and replaced with either a nasal cannula or a non-rebreather mask. Continuous monitoring of the patient’s respiratory status should continue with transport to an appropriate hospital. If the patient continues to present in full cardiac arrest, standard advanced life support should continue with a focus on maintaining a patent airway with high-quality ventilation, oxygenation, and chest compressions.

Naloxone Dosage

The amount of naloxone administration varies greatly depending on the delivery route and the person who is administering the drug. Most lay providers in the community who have Narcan prescribed to them or have received a community Narcan kit deliver 2-4mg either IN or IM. There are risks of delivering such large doses in this manner. Studies have shown there is a risk of flash pulmonary edema, or fluid in the lungs, and catecholamine release that leads to increased cardiovascular blood volume and cardiac dysrhythmia. There is also evidence of increased pulmonary-capillary hydrostatic pressure and increased capillary permeability. For this reason, naloxone should be delivered in lower doses whenever feasible. The 0.4mg IV or IO with repeated bolus is the recommended delivery method; however, the person administering the Narcan must be an advanced medical provider who can initiate IV or IO access. The goal of naloxone administration is not to make the patient fully conscious and alert but to simply supported in respiratory status. If the patient begins to breathe after the initial 0.04mg IV, then the patient should not receive additional doses unless respiratory status declines once again. The goal of naloxone administration should be adequate depth and rate of ventilation rather than a fully alert and oriented patient.

As stated before, local protocols may vary by region or department. Naloxone administration is generally permitted by both basic life support providers and advanced life support providers. Basic life support providers will usually administer Narcan via a nasal mucosal atomizer or pre-filled nasal spray auto-injectors. Advanced life support providers will look to give naloxone IV or IO. The doses for the advanced providers should start with 0.4mg and titrate to effect. The basic life support provider will usually administer 2-4 mg intranasal, with 1-2 mg in each nostril if possible. Basic airway measures will also be part of the protocol, which includes: opening the airway with a head-tilt chin-lift if no trauma is suspected, the adding of either an NPA or OPA, and manual ventilation with a BVM connected to high-flow oxygen. Doses can be repeated up to 3 times or a maximum of 10mg. If more is needed, medical control should be contacted. Reversal of respiratory depression should be the main goal. With the addition of intranasal and intraosseous administration, both IM and ETT administration have been decreased significantly.

The risk of dirty needle poke makes IM administration more dangerous for the first responder. It is also much harder for the community layperson to deliver. ETT administration has to be forcefully manually dispersed with manual ventilation with a BVM and the effects are slow and inconsistent. The patient also risks aspiration pneumonia following ETT administration. Many protocols have deleted ETT administration completely from their protocols. Protocols may also warn or state that intubation is contraindicated following naloxone administration and can only be done with patients who have suffered complete cardiac arrest or medical control must be contacted. The protocol may also mention the need to obtain both a blood glucose level to rule out hypoglycemia as the underlying reason for patient hypoxia, depressed respiratory status, and altered mental status. The advanced provider should also obtain a 12 lead ECG to further evaluate for cardiac dysrhythmia. All doses should be given in 5-minute increments. Patients in full cardiac arrest should be treated with regular cardiac arrest protocols. Heavy emphasis should remain on high-quality compressions, early defibrillation, and high-quality ventilation and oxygenation with basic airway adjuncts in place. Patients who achieve out-of-hospital return of spontaneous circulation but do not begin to have spontaneous breathing can be considered for advanced airway procedures.

Some areas will automatically send both fire and police to the scene of a suspected opioid overdose. Those first responders may also have administered Narcan via their protocols. Many times, they arrive before EMS; therefore, EMS should ascertain if Narcan administration was delivered prior to their arrival by either a lay provider or other responding first responders. Manual ventilation will usually be provided by responding fire departments, but many law enforcement departments do not have proper medical equipment to provide BVM ventilation with high-flow oxygen. If this is the case, the EMS provider should begin high-flow oxygenation with manual BVM ventilation as quickly as possible. If, after several minutes, manual ventilation does not improve the patient’s respiratory status, then EMS providers can begin to administer their own Narcan based on their protocols and provider level. If you work for a combination fire and EMS department, the protocols should be very similar to EMS stand-alone departments.

Naloxone Side Effects

One of the side effects of Narcan administration is agitation in the patient. Often patients regain consciousness and awake agitated. They have lost their “high” and are suddenly thrown into withdrawal. The patient may present initially as confused and start showing signs and symptoms of withdrawal. Patients may experience tachycardia, nausea, and vomiting. Severe agitation or aggression may be noted. The patient may not want to comply with the medical provider’s instructions and try to refuse transport. They often try to leave the scene before law enforcement arrives; if they still have drug paraphernalia on them, they may be cited and ticketed to appear in court, or their belongings may be confiscated. Many patients will try to deny illegal drug use once they are revived.

Increased blood pressure may be seen due to the high catecholamine release. Headache and muscle pain are lower-risk side effects, while pulmonary edema, seizure, and cardiac dysrhythmia are more severe and will require further medical evaluation and treatment. A first responder should be keenly aware of the risks of personal injury when an opioid overdose patient receives naloxone after presenting in respiratory or cardiac arrest and regains consciousness.

One of the more serious side effects that can be seen, especially with higher initial doses of naloxone, is flash pulmonary edema. Several studies suggest a large catecholamine surge that can result in pulmonary edema and cardiac dysrhythmia. Aspiration pneumonia is also a negative side effect seen in many patients who receive larger doses of initial Narcan administration. There does seem to be a correlation to post-operative administration of naloxone and noticeable pulmonary edema. Many patients with this specific side effect received naloxone after receiving opioid analgesia, such as fentanyl for a surgical procedure. There is, of course, risk as well with out-of-hospital opioid use, especially given the rise in heroin that has been laced with fentanyl or carfentanil.

Flash pulmonary edema after naloxone administration has been noted as far back as 1880. However, the risk of death or further complications associated with opioid overdose without naloxone outweighs the risks of flash pulmonary edema. Patients will notably present with pink frothy sputum and hypoxia despite oxygen delivery after Narcan administration. The pre-hospital provider should quickly assess the patient, and increasing hypoxemia and continuous positive airway pressure (CPAP) should be initiated to combat the fluid buildup in the lungs. If there is no improvement with CPAP, the next step would be to consider endotracheal intubation. Providers should be keenly aware to keep vigilant to the patient’s airway and understand the possibility of negative pulmonary side effects. With the community-acquired naloxone kits, the patient may have been given one or several doses of naloxone prior to EMS arrival, and there is evidence to support that high doses may lead to non-cardiac pulmonary edema or aspiration.

Seizures have also been noted after naloxone administration, but this is likely due to the hypoxia the patient suffered. The combination use of other illegal drug substances, such as cocaine, may play a role in seizure activity after administration. As stated previously, there is thought to be a catecholamine surge with naloxone administration that can be controlled with hyperventilation with oxygenation for several minutes prior to Narcan administration. In the case of naloxone administration and seizure, be aware that the administration of Versed or Ativan would not be blocked by prior naloxone administration. Narcan should have no effect on benzodiazepines.

Another keen issue that pre-hospital providers may find after administration of Narcan is a patient who now wants to sign against medical advice and avoid being transported to the hospital. While there is risk of the Narcan wearing off before the opioid has completely left their system, associated deaths after naloxone administration appear to remain low in most studies. Some states or local law enforcement require all patients treated with naloxone to be transported to the hospital, even if it is necessary to do so under a mental health arrest. Therefore, patients do not have the choice of signing against medical advice and receiving ongoing observation for a minimum of 2-4 hours from ED admission. At that point, if the patient has not shown any further respiratory depression episodes, they are safely discharged from the emergency room.

If protocols and policies do not include mandatory transport after Narcan administration, the pre-hospital provider can consider consulting with online medical direction to further protect the medical provider from later legal complications if death or unwanted side effects cause severe medical disability. This does not, however, erase the possibility of the patient taking more opioid substances after release from EMS treatment. There have been documented cases of patients leaving the hospital and overdosing a second time. While that does not put the provider at any legal risk, it is something to consider when signing a patient against medical advice. Once naloxone has been administered, the noted effects of the opioids are now blocked. The patient may want to replicate the feelings and take more opioids to regain the previous feelings of “high.” There is a real risk of an overdose a second time, either by the longer standing opioid originally introduced or by secondary introduction of another opioid substance.



The main concern with any opioid overdose should always be providing high-quality manual ventilation with high-flow oxygen to any patient presenting with respiratory depression. For any patient presenting in cardiac arrest, standard life-saving protocols should be initiated and maintained until the patient achieves a return of spontaneous circulation or field termination has been performed. Always be vigilant of scene safety and remember that the patient may become violent or combative. Dirty needles may be on scene as well and can pose a threat of infectious disease.

As first responder providers, we are generally the first-line medical providers these patients see and our treatment and attitude can have great impact on the overall patient care and the patient’s ability to overcome opioid overdose and addiction.

For more EMS continuing education online, explore our EMS recertifications and group CE solutions for emergency departments.


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Kuo Downing-Reese is a 16-year veteran of EMS. She started her career in Los Angeles County in a variety of settings, including private ambulance, fire, and hospital ED. Kuo went to paramedic school at UCLA-Daniel Freeman. She has a degree in EMS management from George Washington University and currently practices as a full-time critical care paramedic in Rochester, New York. She also does a variety of EMS and medical training as a NYS Certified Lab Instructor (CIC intern), NAEMT instructor, and as AHA regional/training center faculty.



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