Be Ready.
Act Fast.
Save a Life.
REZENOPY™ is an FDA-approved emergency treatment for suspected opioid overdose—available by prescription from your healthcare provider.
If you suspect an opioid overdose,
call 911 immediately.
REZENOPY™ is an emergency medicine — not a substitute for emergency medical care. Always call 911 first, then administer REZENOPY while awaiting help.
Do not leave the person alone.
What is REZENOPY?
Understanding REZENOPY™
REZENOPY (naloxone HCl) Nasal Spray 10 mg is an FDA-approved medicine designed to reverse the life-threatening effects of an opioid overdose quickly and effectively.
What It Is
REZENOPY is a single-dose nasal spray containing 10 mg of naloxone hydrochloride — the highest FDA-approved dose for a naloxone nasal spray available in the United States. Naloxone is a medicine that can temporarily reverse an opioid overdose.1*
*The clinical significance of a higher dose is currently unknown.
How It Works
Naloxone temporarily blocks the effects of opioids in the brain. When someone is experiencing an overdose, REZENOPY can restore normal breathing and can temporarily restore consciousness. It begins working quickly after administration.
Who It’s For
REZENOPY is indicated for adults and pediatric patients when an opioid overdose is known or suspected.1 It is intended for use in settings where opioids may be present — by bystanders, caregivers, family members, and first responders.
Easy to Use
REZENOPY requires no assembly, no needles, and no special training to use. The device is designed to be used in an emergency by anyone. Family members, caregivers, or other people who may have to use REZENOPY nasal spray in an opioid emergency should know where REZENOPY nasal spray is stored and how to give it before an opioid emergency happens. A Quick Start Guide is available for reference.
How to Use
Using REZENOPY™ in an Emergency
If you think someone is experiencing an opioid overdose, act immediately. REZENOPY is designed to be used right away — no assembly required.
- Call 911: Call emergency services immediately. REZENOPY does not replace emergency medical care.
- Position the Person: Lay them on their back. Tilt their head back slightly to open the airway.5
- Administer REZENOPY: Insert the nozzle into one nostril. Press the plunger firmly to release the full dose.5
- Wait & Monitor: Watch for response. If there is no response after 2–3 minutes, an additional dose of naloxone may be given if available and per medical guidance.5
- Stay With Them: Do not leave the person alone. Continue to support their airway until emergency services arrive.
Important:
Naloxone wears off faster than most opioids. Even if the person responds to REZENOPY, they still need immediate emergency medical evaluation. Always wait for emergency responders.
Where to Buy
Where to Fill Your REZENOPY™ Prescription
REZENOPY is available by prescription only. Talk to your healthcare provider about whether REZENOPY is right for you, then ask your pharmacist about how to fill your prescription.
Local Pharmacies
REZENOPY is available at retail and independent pharmacies with a valid prescription. Ask your pharmacist about filling your prescription and whether your insurance plan covers REZENOPY.
Online & Mail-Order
REZENOPY may be available through select online and mail-order pharmacies with a valid prescription. Check with your insurer or pharmacy benefits manager for coverage and fulfillment options.
Talk to Your Doctor
Your healthcare provider can prescribe REZENOPY directly. If you or someone you care for may be at risk for an opioid overdose, ask your doctor whether having naloxone on hand is right for you.
Community Programs
Many communities offer free or reduced-cost naloxone through harm reduction programs, health departments, and outreach organizations. Contact your local health department to learn what is available in your area.
Patient Resources
Equipping yourself and your loved ones with the right information is essential to reducing opioid overdose deaths in today’s fentanyl-driven landscape. The resources below are designed to provide support with practical tools and evidence-based education.
Patient FAQs
REZENOPY (naloxone hydrochloride) nasal spray is a prescription medicine used to temporarily reverse the effects of opioid overdose in adults and children.1 It's designed for emergency treatment of known or suspected opioid overdose with signs of breathing problems and severe sleepiness or unresponsiveness.
Use REZENOPY immediately if you or your caregiver suspect an opioid emergency, even if you’re not completely sure. Signs of an opioid emergency include:
- Unusual sleepiness where the person cannot be awakened with a loud voice or by rubbing firmly on their chest
- Breathing problems, including slow or shallow breathing
- Very small “pinpoint pupils”
- The person appears not to be breathing or is difficult to awaken
Each REZENOPY nasal spray contains one dose and cannot be reused.
- Lay the person on their back
- Support their neck with your hand and tilt their head back
- Give the spray into one nostril
- Call 911 immediately after giving the first dose
- If needed, give additional doses every 2 to 3 minutes in the other nostril using a new spray
For illustrations and step-by-step instructions, download the Quick Start Guide.
Call 911 or get emergency medical help right away after giving the first dose, even if the person wakes up. REZENOPY does not replace emergency medical care. You may also need to perform rescue breathing or CPR while waiting for help to arrive.
Yes, the signs and symptoms of an opioid emergency can return after REZENOPY is given. If this happens, give another dose every 2 to 3 minutes using a new nasal spray and watch the person closely until emergency help arrives.1
Do not use REZENOPY if you are allergic to naloxone hydrochloride or any of the ingredients in the nasal spray.1
REZENOPY 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 REZENOPY nasal spray and may include:
- body aches
- diarrhea
- increased heart rate
- fever
- runny nose
- sneezing
- goose bumps
- sweating
- yawning
- nausea or vomiting
- nervousness
- restlessness or irritability
- shivering or trembling
- stomach cramping
- weakness
- 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.
The most common side effects of REZENOPY nasal spray include: upperstomach-area (abdominal) pain, the common cold, and changes in sense of taste.
These are not all the possible side effects of REZENOPY nasal spray.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1 800-FDA-1088.
- Store at room temperature between 2°C to 25°C (36°F to 77°F)1
- Do not freeze or expose to heat above 40°C (104°F)1
- Keep in its box until ready to use to protect from light1
- Replace before the expiration date1
- Keep out of reach of children1
Yes, if you've been prescribed REZENOPY, you should always carry it with you in case of an opioid emergency.
Yes, family members, caregivers, or others who may need to use REZENOPY in an emergency should know where it's stored and how to use it before an emergency happens.
No, the medicine in REZENOPY has no effect in people who are not taking opioid medicines.
Yes, REZENOPY is safe and effective in children for known or suspected opioid overdose.1
Tell your healthcare provider if you:
- Have heart problems
- Are breastfeeding or plan to breastfeed (it's unknown if REZENOPY passes into breast milk)
- Take any prescription or over-the-counter medicines, vitamins, or herbal supplements
For more information, visit REZENOPY.com. You can also talk to your healthcare provider or pharmacist, or report side effects to the FDA at 1-800-FDA-1088.
References
- REZENOPY™ (naloxone HCl) nasal spray 10 mg [prescribing information]. Commack, NY; Scienture, LLC 2025.
- Provisional drug overdose death counts. National Center for Health Statistics, Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/nchs/nvss/vsrr/drug-overdose-data.htm. Accessed March 2026.
- Substance Abuse and Mental Health Services Administration. (2025). Key substance use and mental health indicators in the United States: Results from the 2024 National Survey on Drug Use and Health. HHS Publication No. PEP25-07-007, NSDUH Series H-60.
- Fentanyl (2025) National Institute on Drug Abuse website. Available at: https://nida.nih.gov/research-topics/fentanyl. Accessed: March 2026.
- REZENOPY™ Quick Start Guide. Commack, NY; Scienture, LLC 2025.
