This is a news article about fentanyl overdoses. In the event of an actual overdose, stop reading, call 911, and seek immediate medical assistance.
Part III of a 4-part series.
Narcan (naloxone) Dosage
Narcan (naloxone) is an FDA approved nasal spray used to treat a known or suspected opioid overdose emergency.
The intranasal Narcan (naloxone) used at New Rochelle High School is 4 mg, which is 10 times the dose used in a post-operative setting.
One dose of 4 mg is more than enough to cause a patient to awaken, but increases the risk of Negative Pressure Pulmonary Edema.
The intranasal Narcan (naloxone) dose 4 mg = 4000 mcg.
Pharmacologically, a topical dose would have to be higher than an intravenous dose for the same effectiveness, owing to skin as a barrier and liver that will metabolize. In the case of intranasal Narcan (naloxone) dosing, that is directly applied to neural tissue (sphenopalatine ganglion in the nose, sclera of the eyes) the application avoids liver metabolism, diffusion across skin, and is directly applied to brain, absorbed into the vasculature of the nose.
4 mg Intranasal Narcan (naloxone) is a high dose which will last about 60 minutes.
Multiple consecutive (never concurrent) doses may be required, as the duration of action of some opioids is longer than that of Narcan (naloxone).
Narcan (naloxone) Can Cause Death
Narcan (naloxone) should be administered by a medical professional or someone trained in the use of Narcan (naloxone) such as a police officer.
A single dose of Narcan (naloxone) is 40 mcg when administered intravenously, for example in a hospital. It is packaged as 400 mcg (0.4 mg) and diluted 1:10. There is no more effectiveness at higher doses because one such dose is a high amount.
Narcan (naloxone) should never be administered in multiple concurrent doses.
Narcan (naloxone) is a competitive inhibitor with the opioid at the mu receptor level.
When reviving someone who has overdosed or is overly sedated post-op in the recovery room, there is a risk of Negative Pressure Pulmonary Edema (a sudden sympathetic surge at the level of the hypothalamus; fluid accumulates in the lungs and must be intubated immediately).
Negative Pressure Pulmonary Edema
Pulmonary edema is a condition caused by too much fluid in the lungs. This fluid collects in the many air sacs in the lungs, making it difficult to breathe. In most cases, heart problems cause pulmonary edema. But fluid can collect in the lungs for other reasons. These include pneumonia, contact with certain toxins, medications, trauma to the chest wall, and traveling to or exercising at high elevations. Pulmonary edema that develops suddenly (acute pulmonary edema) is a medical emergency that needs immediate care. Pulmonary edema can sometimes cause death. Prompt treatment might help. Treatment for pulmonary edema depends on the cause, but generally includes additional oxygen and medications.
NIH: Naloxone induced pulmonary edema
Naloxone-induced noncardiogenic pulmonary edema is a rare but reported entity that can occur following naloxone use in the reversal of opioid overdose. Proposed mechanisms include an adrenergic crisis secondary to catecholamine surge which causes more volume shift to pulmonary vasculature, subsequently leading to pulmonary edema. It appears to be more common when higher doses of naloxone are used. We present a case of a patient with opioid overdose came with altered mental status developed early features of pulmonary edema following the administration of multiple doses of naloxone. She responded well with the administration of diuretics and oxygen supplementation. Her oxygen requirements improved and didn’t require mechanical ventilation.
NIH: Naloxone-associated pulmonary edema following recreational opioid overdose
Severe acute pulmonary edema may follow naloxone administration after recreational opioid overdose. Acute care clinicians should be aware of this potentially life-threatening adverse effect of naloxone.
This conclusion is based on a study published by the National Institute of Health which looked at 10 adults with recreational opioid overdose who developed naloxone-associated pulmonary edema, defined as the acute onset of respiratory distress, hypoxemia, and radiographic pulmonary edema after naloxone administration for opioid intoxication. Ten adults (median age 23 years, 90% male) met the case definition for naloxone-associated pulmonary edema. Implicated opioids were heroin in 8 patients and methadone and oxycodone in 1 patient each. The median total dose of naloxone was 4.25 mg before the onset of clinically apparent pulmonary edema. Seven patients received invasive mechanical ventilation for a median of two days, one of whom received veno-venous extracorporeal membrane oxygenation support (ECMO), and all survived to hospital discharge.