Warnings for Narcan Nasal
Included as part of the "PRECAUTIONS" Section
Precautions for Narcan Nasal
Risk Of Recurrent Respiratory And Central Nervous System Depression
The duration of action of most opioids may exceed that of NARCAN Nasal Spray resulting in a return of respiratory and/or central nervous system depression after an initial improvement in symptoms. Therefore, it is necessary to seek emergency medical assistance immediately after administration of the first dose of NARCAN Nasal Spray and to keep the patient under continued surveillance. Administer additional doses of NARCAN Nasal Spray if the patient is not adequately responding or responds and then relapses back into respiratory depression, as necessary [see DOSAGE AND ADMINISTRATION]. Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance.
Risk Of Limited Efficacy With Partial Agonists Or Mixed Agonist/Antagonists
Reversal of respiratory depression by partial agonists or mixed agonist/antagonists such as buprenorphine and pentazocine, may be incomplete. Larger or repeat doses of naloxone hydrochloride may be required to antagonize buprenorphine because the latter has a long duration of action due to its slow rate of binding and subsequent slow dissociation from the opioid receptor [see DOSAGE AND ADMINISTRATION]. Buprenorphine antagonism is characterized by a gradual onset of the reversal effects and a decreased duration of action of the normally prolonged respiratory depression.
Precipitation Of Severe Opioid Withdrawal
The use of NARCAN Nasal Spray in patients who are opioid-dependent may precipitate opioid withdrawal characterized by the following signs and symptoms: body aches, diarrhea, tachycardia, fever, runny nose, sneezing, piloerection, sweating, yawning, nausea or vomiting, nervousness, restlessness or irritability, shivering or trembling, abdominal cramps, weakness, and increased blood pressure. In neonates, opioid withdrawal may be life-threatening if not recognized and properly treated and may include the following signs and symptoms: convulsions, excessive crying, and hyperactive reflexes. Monitor the patient for the development of the signs and symptoms of opioid withdrawal.
Abrupt postoperative reversal of opioid depression after using naloxone hydrochloride may result in nausea, vomiting, sweating, tremulousness, tachycardia, hypotension, hypertension, seizures, ventricular tachycardia and fibrillation, pulmonary edema, and cardiac arrest. Death, coma, and encephalopathy have been reported as sequelae of these events. These events have primarily occurred in patients who had pre-existing cardiovascular disorders or received other drugs that may have similar adverse cardiovascular effects. Although a direct cause and effect relationship has not been established, after use of naloxone hydrochloride, monitor patients with pre-existing cardiac disease or patients who have received medications with potential adverse cardiovascular effects for hypotension, ventricular tachycardia or fibrillation, and pulmonary edema in an appropriate healthcare setting. It has been suggested that the pathogenesis of pulmonary edema associated with the use of naloxone hydrochloride is similar to neurogenic pulmonary edema, i.e., a centrally mediated massive catecholamine response leading to a dramatic shift of blood volume into the pulmonary vascular bed resulting in increased hydrostatic pressures.
There may be clinical settings, particularly the postpartum period in neonates with known or suspected exposure to maternal opioid use, where it is preferable to avoid the abrupt precipitation of opioid withdrawal symptoms. In these settings, consider use of an alternative, naloxone-containing product that can be titrated to effect and, where applicable, dosed according to weight. [see Use In Specific Populations].
Patient Counseling Information
Advise the patient and family members or caregivers to read the FDA-approved patient labeling (PATIENT INFORMATION and Instructions for Use).
Recognition Of Opioid Overdose
Inform patients and their family members or caregivers about how to recognize the signs and symptoms of an opioid overdose such as the following:
- Extreme somnolence - inability to awaken a patient verbally or upon a firm sternal rub.
- Respiratory depression - this can range from slow or shallow respiration to no respiration in a patient who is unarousable.
- Other signs and symptoms that may accompany somnolence and respiratory depression include the following:
- Miosis.
- Bradycardia and/or hypotension.
Risk Of Recurrent Respiratory And Central Nervous System Depression
Instruct patients and their family members or caregivers that, since the duration of action of most opioids may exceed that of NARCAN Nasal Spray, they must seek immediate emergency medical assistance after the first dose of NARCAN Nasal Spray and keep the patient under continued surveillance [see DOSAGE AND ADMINISTRATION, WARNINGS AND PRECAUTIONS].
Limited Efficacy For/With Partial Agonists Or Mixed Agonist/Antagonists
Instruct patients and their family members or caregivers that the reversal of respiratory depression caused by partial agonists or mixed agonist/antagonists, such as buprenorphine and pentazocine, may be incomplete and may require higher doses of naloxone hydrochloride or repeated administration of NARCAN Nasal Spray, using a new nasal spray each time [see DOSAGE AND ADMINISTRATION, WARNINGS AND PRECAUTIONS].
Precipitation Of Severe Opioid Withdrawal
Instruct patients and their family members or caregivers that the use of NARCAN Nasal Spray in patients who are opioid dependent may precipitate opioid withdrawal [see WARNINGS AND PRECAUTIONS, ADVERSE REACTIONS].
Administration Instructions
Instruct patients and their family members or caregivers to:
- Ensure NARCAN Nasal Spray is present whenever persons may be intentionally or accidentally exposed to an opioid overdose (i.e., opioid emergencies).
- Administer NARCAN Nasal Spray as quickly as possible if a patient is unresponsive and an opioid overdose is suspected, even when in doubt, because prolonged respiratory depression may result in damage to the central nervous system or death. NARCAN Nasal Spray is not a substitute for emergency medical care [see DOSAGE AND ADMINISTRATION].
- Lay the patient on their back and administer NARCAN Nasal Spray into one nostril while providing support to the back of the neck to allow the head to tilt back [see DOSAGE AND ADMINISTRATION].
- Use each nasal spray only one time [see DOSAGE AND ADMINISTRATION].
- Turn patient on their side as shown in the Instructions for Use and call for emergency medical assistance immediately after administration of the first dose of NARCAN Nasal Spray. Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance [see DOSAGE AND ADMINISTRATION].
- Monitor patients and re-administer NARCAN Nasal Spray using a new NARCAN Nasal Spray every 2 to 3 minutes, if the patient is not responding or responds and then relapses back into respiratory depression. Administer NARCAN Nasal Spray in alternate nostrils with each dose [see DOSAGE AND ADMINISTRATION].
- Replace NARCAN Nasal Spray before its expiration date.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Carcinogenesis
Long-term animal studies to evaluate the carcinogenic potential of naloxone have not been completed.
Mutagenesis
Naloxone was weakly positive in the Ames mutagenicity and in the in vitro human lymphocyte chromosome aberration test but was negative in the in vitro Chinese hamster V79 cell HGPRT mutagenicity assay and in the in vivo rat bone marrow chromosome aberration study.
Impairment Of Fertility
Male rats were treated with 2 or 10 mg/kg naloxone for 60 days prior to mating. Female rats treated for 14-days prior to mating and throughout gestation with the same doses of naloxone (up to 12-times a human dose of 8 mg/day (two NARCAN Nasal Sprays) based on body surface area comparison). There was no adverse effect on fertility.
Use In Specific Populations
Pregnancy
Risk Summary
The limited available data on naloxone use in pregnant women are not sufficient to inform a drugassociated risk. However, there are clinical considerations [see Clinical Considerations]. In animal reproduction studies, no embryotoxic or teratogenic effects were observed in mice and rats treated with naloxone hydrochloride during the period of organogenesis at doses equivalent to 6-times and 12- times, respectively, a human dose of 8 mg/day (two NARCAN Nasal Sprays) based on body surface area comparison [see Data].
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Clinical Considerations
Fetal/Neonatal adverse reactions
Naloxone hydrochloride crosses the placenta, and may precipitate withdrawal in the fetus, as well as in the opioid-dependent mother [see WARNINGS AND PRECAUTIONS]. The fetus should be evaluated for signs of distress after NARCAN Nasal Spray is used. Careful monitoring is needed until the fetus and mother are stabilized.
Data
Animal Data
Naloxone hydrochloride was administered during organogenesis to mice and rats at subcutaneous doses up to 10 mg/kg/day (equivalent to 6-times and 12-times, respectively, a human dose of 8 mg (two NARCAN Nasal Sprays)) (based on body surface area comparison). These studies demonstrated no embryotoxic or teratogenic effects due to naloxone hydrochloride.
Pregnant female rats were administered 2 or 10 mg/kg naloxone subcutaneously from Gestation Day 15 to Postnatal day 21. There were no adverse effects on the offspring (up to 12-times a human dose of 8 mg/day (two NARCAN Nasal Spray) based on body surface area comparison).
Lactation
Risk Summary
There is no information regarding the presence of naloxone in human milk, or the effects of naloxone on the breastfed infant or on milk production. Studies in nursing mothers have shown that naloxone does not affect prolactin or oxytocin hormone levels. Naloxone is minimally orally bioavailable.
Pediatric Use
The safety and effectiveness of NARCAN Nasal Spray have been established in pediatric patients of all ages for known or suspected opioid overdose as manifested by respiratory and/or central nervous system depression. Use of naloxone hydrochloride in all pediatric patients is supported by adult bioequivalence studies coupled with evidence from the safe and effective use of other naloxone hydrochloride drug products. No pediatric studies were conducted for NARCAN Nasal Spray.
Absorption of naloxone hydrochloride following intranasal administration in pediatric patients may be erratic or delayed. Even when the opiate-intoxicated pediatric patient responds appropriately to naloxone hydrochloride, he/she must be carefully monitored for at least 24 hours, as a relapse may occur as naloxone hydrochloride is metabolized.
In opioid-dependent pediatric patients, (including neonates), administration of naloxone hydrochloride may result in an abrupt and complete reversal of opioid effects, precipitating an acute opioid withdrawal syndrome. Neonatal opioid withdrawal syndrome, unlike opioid withdrawal syndrome in adults, may be life-threatening, if not recognized, and should be treated according to protocols developed by neonatology experts [see WARNINGS AND PRECAUTIONS].
In settings such as in neonates with known or suspected exposure to maternal opioid use, where it may be preferable to avoid the abrupt precipitation of opioid withdrawal symptoms, consider use of an alternate naloxone-containing product that can be dosed according to weight and titrated to effect.
Also, in situations where the primary concern is for infants at risk for opioid overdose, consider whether the availability of alternate naloxone-containing products may be better suited than NARCAN Nasal Spray.
Geriatric Use
Geriatric patients have a greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy. Therefore, the systemic exposure of naloxone hydrochloride can be higher in these patients.
Clinical studies of naloxone hydrochloride did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients.