al opioid exposure by household contacts.

may result in adverse cv effects. these events have primarily occurred in patients who had pre-existing cv disorders or received other drugs that may have similar adverse cv effects. monitor these patients closely in an appropriate healthcare setting after use of naloxone hydrochloride. ( 5.3 ) 5.1 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 (2.2) ] . additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance. 5.2 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 (2.3) ] . buprenorphine antagonism is characterized by a gradual onset of the reversal effects and a decreased duration of action of the normally prolonged respiratory depression. 5.3 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. there are limited data to inform if the 2 mg dose of narcan nasal spray will avoid precipitation of severe opioid withdrawal in the setting of opioid dependence. however, the 2 mg dose may not provide an adequate and timely reversal in persons who may be exposed to an overdose of a potent or very high dose of opioids. 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 (8.4) ] .

the presence of narcan nasal spray and the instructions for use. instruct the patient or caregiver to read the instructions for use at the time they receive a prescription for narcan nasal spray. emphasize the following instructions to the patient or caregiver: • administer narcan nasal spray as quickly as possible because prolonged respiratory depression may result in damage to the central nervous system or death. since the duration of action of most opioids exceeds that of naloxone hydrochloride and the suspected opioid overdose may occur outside of supervised medical settings, seek immediate emergency medical assistance, keep the patient under continued surveillance until emergency personnel arrive, and administer repeated doses of narcan nasal spray, as necessary. always seek emergency medical assistance in the event of a suspected, potentially life-threatening opioid emergency after administration of the first dose of narcan nasal spray. • additional doses of narcan nasal spray may be required until emergency medical assistance becomes available. • do not attempt to reuse narcan nasal spray. each narcan nasal spray contains a single dose of naloxone and cannot be reused. • re-administer narcan nasal spray, using a new nasal spray, every 2 to 3 minutes if the patient does not respond or responds and then relapses into respiratory depression. • administer narcan nasal spray in alternate nostrils with each dose. • administer narcan nasal spray according to the printed instructions on the device label and the instructions for use . • place the patient in the supine position. prior to administration, be sure the device nozzle is inserted in either nostril of the patient, and provide support to the back of the neck to allow the head to tilt back. do not prime or test the device prior to administration. • to administer the dose press firmly on the device plunger. • remove the device nozzle from the nostril after use. • 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. 2.2 dosing in adults and pediatric patients initial dosing the recommended initial dose of narcan nasal spray in adults and pediatric patients is one spray delivered by intranasal administration into one nostril. repeat dosing seek emergency medical assistance as soon as possible after administering the first dose of narcan nasal spray. the requirement for repeat doses of narcan nasal spray depends upon the amount, type, and route of administration of the opioid being antagonized. administer narcan nasal spray in alternate nostrils with each dose. if the patient responds to narcan nasal spray and relapses back into respiratory depression before emergency assistance arrives, administer an additional dose of narcan nasal spray using a new narcan nasal spray and continue surveillance of the patient. if the desired response is not obtained after 2 or 3 minutes, administer an additional dose of narcan nasal spray using a new narcan nasal spray. if there is still no response and additional doses are available, administer additional doses of narcan nasal spray every 2 to 3 minutes using a new narcan nasal spray with each dose until emergency medical assistance arrives. additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance. 2.3 dosing modifications due to 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 and require higher doses of naloxone hydrochloride or repeated administration of narcan nasal spray using a new nasal spray [see warnings and precautions (5.2) ] .

d primarily during post-approval use of naloxone hydrochloride in the post-operative setting. because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: hypotension, hypertension, ventricular tachycardia and fibrillation, dyspnea, pulmonary edema, and cardiac arrest. death, coma, and encephalopathy have been reported as sequelae of these events. excessive doses of naloxone hydrochloride in post-operative patients have resulted in significant reversal of analgesia, and have caused agitation. abrupt reversal of opioid effects in persons who were physically dependent on opioids has precipitated an acute withdrawal syndrome. signs and symptoms have included: body aches, fever, sweating, runny nose, sneezing, piloerection, yawning, weakness, shivering or trembling, nervousness, restlessness or irritability, diarrhea, nausea or vomiting, abdominal cramps, increased blood pressure, tachycardia. in some patients, there may be aggressive behavior upon abrupt reversal of an opioid overdose. in the neonate, opioid withdrawal signs and symptoms also included convulsions, excessive crying, and hyperactive reflexes. the following adverse reactions were observed in a narcan nasal spray clinical study: increased blood pressure, constipation, toothache, muscle spasms, musculoskeletal pain, headache, nasal dryness, nasal edema, nasal congestion, nasal inflammation, rhinalgia, and xeroderma. ( 6 ) to report suspected adverse reactions, contact emergent devices inc. at 1-844-4narcan (1-844-462-7226) or fda at 1-800-fda-1088 or www.fda.gov/medwatch .

wal in the fetus, as well as in the opioid-dependent mother [see warnings and precautions (5.3) ] . 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). 8.2 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. 8.4 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 (5.3) ] . 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. 8.5 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.

n the opioid-dependent mother [see warnings and precautions (5.3) ] . 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).

d 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 (5.3) ] . 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.

d a 4 mg total dose (0.1 ml of 40 mg/ml naloxone hydrochloride solution), and two nasal sprays administered as one nasal spray in each nostril, consisting of a 4 mg total dose (0.1 ml of 20 mg/ml naloxone hydrochloride solution in each nostril) and an 8 mg total dose (0.1 ml of 40 mg/ml naloxone hydrochloride solution in each nostril), were compared to a single dose of 0.4 mg naloxone hydrochloride intramuscular injection. for intranasal administration, the subjects were instructed not to breathe through the nose during administration of the nasal spray, and remained fully supine for approximately one hour post-dose. for intramuscular administration, naloxone was administered as a single injection in the gluteus maximus muscle. the pharmacokinetic parameters obtained in the study are shown in table 1. table 1 mean pharmacokinetic parameters (cv%) for naloxone following narcan (naloxone hcl) nasal spray and intramuscular injection of naloxone hcl to healthy subjects parameter 2 mg – one nasal spray in one nostril 20 mg/ml (n=29) 4 mg – two nasal sprays, one in each nostril 20 mg/ml (n=29) 4 mg – one nasal spray in one nostril 40 mg/ml (n=29) 8 mg –two nasal sprays, one in each nostril 40 mg/ml (n=29) 0.4 mg intramuscular injection (n=29) t max (h) t max reported as median (minimum, maximum) 0.33 (0.25, 1.00) 0.33 (0.17, 0.57) 0.50 (0.17, 1.00) 0.33 (0.17, 1.00) 0.38 (0.08, 2.05) c max (ng/ml) 2.91 (35) 6.30 (34) 4.83 (43) 9.70 (36) 0.88 (31) auct (hr.ng/ml) 4.60 (27) 9.64 (24) 7.87 (37) 15.3 (23) 1.75 (23) auc 0-inf (h*ng/ml) 4.66 (27) 9.74 (24) 7.95 (37) 15.5 (23) 1.79 (23) t½ (h) 1.85 (33) 2.19 (33) 2.08 (30) 2.10 (32) 1.24 (26) dose normalized relative ba (%) vs. im 51.7 (22) 54.0 (23) 44.2 (31) n=28 for relative ba. 43.1 (24) 100 figure 1 mean ± sd plasma concentration of naloxone, (a) 0-6 h and (b) 0-1h following intranasal administration and intramuscular injection (a) figure 1 mean ± sd plasma concentration of naloxone, (a) 0-6 h and (b) 0-1h following intranasal administration and intramuscular injection (b) figure 1 mean ± sd plasma concentration of naloxone, (a) 0-6 h and (b) 0-1h following intranasal administration and intramuscular injection the median naloxone t max after intranasal administration of narcan nasal spray (one nasal spray in one nostril (2 mg or 4 mg) or two nasal sprays as one spray in each nostril (4 mg or 8 mg) was not significantly different compared to the 0.4 mg dose of naloxone hydrochloride intramuscular injection (table 1). the dose normalized relative bioavailability of one dose (2 mg or 4 mg) or two doses (4 mg or 8 mg) of narcan nasal spray as compared to the 0.4 mg dose of naloxone hydrochloride administered by intramuscular injection was 52%, 44%, 54%, and 43%, respectively. distribution following parenteral administration, naloxone is distributed in the body and readily crosses the placenta. plasma protein binding occurs but is relatively weak. plasma albumin is the major binding constituent, but significant binding of naloxone also occurs to plasma constituents other than albumin. it is not known whether naloxone is excreted into human milk. elimination following a single intranasal administration of narcan nasal spray (2 mg or 4 mg dose of naloxone hydrochloride), the mean plasma half-life of naloxone in healthy adults was approximately 1.85 (33% cv) hours and 2.08 (30% cv) hours; respectively, which was longer than that observed after administrations of a 0.4 mg naloxone hydrochloride intramuscular injection, where the half-life was 1.24 hours (26% cv). in a neonatal study of naloxone hydrochloride injection, the mean (± sd) plasma half-life was observed to be 3.1 (± 0.5) hours. metabolism naloxone hydrochloride is metabolized in the liver, primarily by glucuronide conjugation, with naloxone-3-glucoronide as the major metabolite. excretion after an oral or intravenous dose, about 25-40% of naloxone is excreted as metabolites in urine within 6 hours, about 50% in 24 hours, and 60-70% in 72 hours. figure 1(a) figure 1(b)

ers obtained in the study are shown in table 1. table 1 mean pharmacokinetic parameters (cv%) for naloxone following narcan (naloxone hcl) nasal spray and intramuscular injection of naloxone hcl to healthy subjects parameter 2 mg – one nasal spray in one nostril 20 mg/ml (n=29) 4 mg – two nasal sprays, one in each nostril 20 mg/ml (n=29) 4 mg – one nasal spray in one nostril 40 mg/ml (n=29) 8 mg –two nasal sprays, one in each nostril 40 mg/ml (n=29) 0.4 mg intramuscular injection (n=29) t max (h) t max reported as median (minimum, maximum) 0.33 (0.25, 1.00) 0.33 (0.17, 0.57) 0.50 (0.17, 1.00) 0.33 (0.17, 1.00) 0.38 (0.08, 2.05) c max (ng/ml) 2.91 (35) 6.30 (34) 4.83 (43) 9.70 (36) 0.88 (31) auct (hr.ng/ml) 4.60 (27) 9.64 (24) 7.87 (37) 15.3 (23) 1.75 (23) auc 0-inf (h*ng/ml) 4.66 (27) 9.74 (24) 7.95 (37) 15.5 (23) 1.79 (23) t½ (h) 1.85 (33) 2.19 (33) 2.08 (30) 2.10 (32) 1.24 (26) dose normalized relative ba (%) vs. im 51.7 (22) 54.0 (23) 44.2 (31) n=28 for relative ba. 43.1 (24) 100 figure 1 mean ± sd plasma concentration of naloxone, (a) 0-6 h and (b) 0-1h following intranasal administration and intramuscular injection (a) figure 1 mean ± sd plasma concentration of naloxone, (a) 0-6 h and (b) 0-1h following intranasal administration and intramuscular injection (b) figure 1 mean ± sd plasma concentration of naloxone, (a) 0-6 h and (b) 0-1h following intranasal administration and intramuscular injection the median naloxone t max after intranasal administration of narcan nasal spray (one nasal spray in one nostril (2 mg or 4 mg) or two nasal sprays as one spray in each nostril (4 mg or 8 mg) was not significantly different compared to the 0.4 mg dose of naloxone hydrochloride intramuscular injection (table 1). the dose normalized relative bioavailability of one dose (2 mg or 4 mg) or two doses (4 mg or 8 mg) of narcan nasal spray as compared to the 0.4 mg dose of naloxone hydrochloride administered by intramuscular injection was 52%, 44%, 54%, and 43%, respectively. distribution following parenteral administration, naloxone is distributed in the body and readily crosses the placenta. plasma protein binding occurs but is relatively weak. plasma albumin is the major binding constituent, but significant binding of naloxone also occurs to plasma constituents other than albumin. it is not known whether naloxone is excreted into human milk. elimination following a single intranasal administration of narcan nasal spray (2 mg or 4 mg dose of naloxone hydrochloride), the mean plasma half-life of naloxone in healthy adults was approximately 1.85 (33% cv) hours and 2.08 (30% cv) hours; respectively, which was longer than that observed after administrations of a 0.4 mg naloxone hydrochloride intramuscular injection, where the half-life was 1.24 hours (26% cv). in a neonatal study of naloxone hydrochloride injection, the mean (± sd) plasma half-life was observed to be 3.1 (± 0.5) hours. metabolism naloxone hydrochloride is metabolized in the liver, primarily by glucuronide conjugation, with naloxone-3-glucoronide as the major metabolite. excretion after an oral or intravenous dose, about 25-40% of naloxone is excreted as metabolites in urine within 6 hours, about 50% in 24 hours, and 60-70% in 72 hours. figure 1(a) figure 1(b)

t away. however, narcan nasal spray may be thawed by allowing it to sit at room temperature for 15 minutes, and it may still be used if it has been thawed after being previously frozen.

ical assistance after the first dose of narcan nasal spray and keep the patient under continued surveillance [see dosage and administration (2.2) , warnings and precautions (5.3) ] . 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 (2.3) , warnings and precautions (5.2) ] . 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 (5.3) , adverse reactions (6) ] . 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 (2.1) ] . • 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 (2.1) ] . • use each nasal spray only one time [see dosage and administration (2.1) ] . • 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 (2.1) ]. • 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 (2.1) ] . • replace narcan nasal spray before its expiration date.

ioid emergency may include: • unusual sleepiness and you are not able to awaken the person with a loud voice or by rubbing firmly on the middle of their chest (sternum) • breathing problems including slow or shallow breathing in someone difficult to awaken or who looks like they are not breathing • the black circle in the center of the colored part of the eye (pupil) is very small, sometimes called "pinpoint pupils," in someone difficult to awaken 2. family members, caregivers, or other people who may have to use narcan nasal spray in an opioid emergency should know where narcan nasal spray is stored and how to give narcan before an opioid emergency happens. 3. get emergency medical help right away after giving the first dose of narcan nasal spray. rescue breathing or cpr (cardiopulmonary resuscitation) may be given while waiting for emergency medical help. 4. the signs and symptoms of an opioid emergency can return after narcan nasal spray is given. if this happens, give another dose after 2 to 3 minutes using a new narcan nasal spray and watch the person closely until emergency help is received. what is narcan nasal spray? • narcan nasal spray is a prescription medicine used for the treatment of an opioid emergency such as an overdose or a possible opioid overdose with signs of breathing problems and severe sleepiness or not being able to respond. • narcan nasal spray is to be given right away and does not take the place of emergency medical care. get emergency medical help right away after giving the first dose of narcan nasal spray, even if the person wakes up. • narcan nasal spray is safe and effective in children for known or suspected opioid overdose. who should not use narcan nasal spray? do not use narcan nasal spray if you are allergic to naloxone hydrochloride or any of the ingredients in narcan nasal spray. see the end of this leaflet for a complete list of ingredients in narcan nasal spray. what should i tell my healthcare provider before using narcan nasal spray? before using narcan nasal spray, tell your healthcare provider about all of your medical conditions, including if you: • have heart problems • are pregnant or plan to become pregnant. use of narcan nasal spray may cause withdrawal symptoms in your unborn baby. your unborn baby should be examined by a healthcare provider right away after you use narcan nasal spray. • are breastfeeding or plan to breastfeed. it is not known if narcan nasal spray passes into your breast milk. tell your healthcare provider about the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. how should i use narcan nasal spray? read the "instructions for use" at the end of this patient information leaflet for detailed information about the right way to use narcan nasal spray. • use narcan nasal spray exactly as prescribed by your healthcare provider. • each narcan nasal spray contains only 1 dose of medicine and cannot be reused. • narcan nasal spray comes in a 2 mg and 4 mg strength. your healthcare provider will prescribe the one that is right for you. • lay the person on their back. support their neck with your hand and allow the head to tilt back before giving narcan nasal spray. • narcan nasal spray should be given into one nostril. • if additional doses are needed, give narcan nasal spray in the other nostril. what are the possible side effects of narcan nasal spray? narcan nasal spray may cause serious side effects, including: 1. sudden opioid withdrawal symptoms. in someone who has been using opioids regularly, opioid withdrawal symptoms can happen suddenly after receiving narcan nasal spray and may include: o body aches o diarrhea o increased heart rate o fever o runny nose o sneezing o goose bumps o sweating o yawning o nausea or vomiting o nervousness o restlessness or irritability o shivering or trembling o stomach cramping o weakness o increased blood pressure in infants under 4 weeks old who have been receiving opioids regularly, sudden opioid withdrawal may be life-threatening if not treated the right way. signs and symptoms include: seizures, crying more than usual, and increased reflexes. these are not all of the possible side effects of narcan nasal spray. call your doctor for medical advice about side effects. you may report side effects to fda at 1-800-fda-1088. how should i store narcan nasal spray? • store below 77°f (25°c). • excursions permitted up to 104°f (40°c). • do not freeze or expose to excessive heat above 104°f (40°c).' • keep narcan nasal spray in its box until ready to use. protect from light. • replace narcan nasal spray before the expiration date on the box. keep narcan nasal spray and all medicines out of the reach of children. general information about the safe and effective use of narcan nasal spray. medicines are sometimes prescribed for purposes other than those listed in a patient information leaflet. do not use narcan nasal spray for a condition for which it was not prescribed. you can ask your pharmacist or healthcare provider for information about narcan nasal spray that is written for health professionals. what are the ingredients in narcan nasal spray? active ingredient: naloxone hydrochloride inactive ingredients: benzalkonium chloride (preservative), disodium ethylenediaminetetraacetate (stabilizer), sodium chloride, hydrochloric acid to adjust ph and sterile water narcan nasal spray is not made with natural rubber latex. distributed by emergent devices inc., plymouth meeting, pa 19462 usa. for more information, go to www.narcan.com or call 1-844-4narcan (1-844-462-7226).