WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
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 Sprays) 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 has
been established in pediatric patients for known or suspected opioid overdose,
as manifested by respiratory and/or central nervous system depression. Use of
naloxone hydrochloride in pediatric patients is supported by evidence from adequate
and well-controlled studies of naloxone hydrochloride in adults with additional
data from 15 clinical studies (controlled and uncontrolled) in which neonates
and pediatric patients received parenteral naloxone hydrochloride in doses ranging
from 0.005 mg/kg to 0.01 mg/kg. Safety and effectiveness are also supported by
use of other naloxone hydrochloride products in the post-marketing setting, as
well as data available in the medical literature and clinical practice
guidelines. NARCAN Nasal Spray may be administered to pediatric patients of all
ages.
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.