How long is Narcan good for?
Narcan nasal spray made since January 2024 is good for 4 years from manufacture. Earlier spray had a 3-year shelf life, and before August 2020 a 2-year one. Whatever the age, the date printed on the box is the one that counts.
The FDA approved Narcan’s first extension, from 2 years to 3, on August 6, 2020. On January 17, 2024, it announced that newly made Narcan 4 mg nasal spray would carry a 4-year shelf life, a change the FDA itself asked for. The longer life applies only to spray made after that announcement; boxes made earlier keep the date already printed on them, and the FDA told users to keep following the printed date.
Narcan became the first naloxone product approved for sale without a prescription on March 29, 2023, so it’s now easy to stock in a school, office or community building. That also means many boxes in circulation were bought at different times, with dates years apart. Check each one.
Other naloxone products don’t publish a shelf life on their labels. Each carries its own printed expiration date, and that’s what to track.
How to find the expiration date on Narcan
Narcan’s box carries the expiration date, and so does each blister pack, beside the lot number. On the blister it reads as year, month and day.
Each Narcan sprayer comes sealed in its own blister pack, printed with its own lot number and date, so a sprayer kept outside its box can still be checked. While you’re looking, confirm the blister isn’t open or torn and the sprayer looks undamaged: the label says not to use Narcan if either is the case.
Prescription naloxone injections print the date as month and year. Zimhi’s label, for example, says to replace it before the last day of the printed month.
Keep a note of each box’s date and lot number in your log or tracking system, so you can see what expires next without opening every cabinet.
Can you use expired Narcan?
The FDA’s position is to follow the date printed on each package. Its general advice on expired medicine is not to use it, because there’s no guarantee it’s still safe and effective after that date. It hasn’t published guidance on using expired naloxone in an emergency.
The FDA explains that an expiration date marks how long the maker has shown a drug keeps its strength and quality when stored as labeled. After that, it may be weaker. Poor storage, such as heat, can weaken a drug even before its date.
The FDA does sometimes extend expiration dates during drug shortages, but only for specific lots it lists, based on the maker’s data. As of September 2026, its list of extended dates included no naloxone products.
The way to avoid the question is to replace naloxone before it expires and keep more than one dose on hand. Whoever responds to a suspected overdose should call 911 as well as give naloxone.
How to store Narcan
Store Narcan between 36 and 77°F (2 and 25°C), at room temperature or in the refrigerator. Don’t freeze it, keep it below 104°F (40°C), and keep it out of the light in its box.
That’s the wording of the over-the-counter Drug Facts label on the box. The prescription Narcan label, which is still published, words it a little differently: store it below 77°F, with short trips up to 104°F allowed. Both say not to freeze it.
Freezing is the main risk in a car or an unheated building. Narcan freezes below 5°F (-15°C), and a frozen sprayer won’t spray. The prescription label says it thaws in about 15 minutes at room temperature and still works afterward, but if someone needs it while it’s frozen, don’t wait: call 911 and get emergency help right away.
Heat is the other risk. A parked car can get hotter than 104°F in summer and colder than 5°F in winter, so it’s a poor place to keep Narcan for long. In a building, keep it somewhere easy to reach, at room temperature and out of direct sunlight, such as a wall cabinet near the AED or a first aid station.
Other naloxone products
Generic 4 mg naloxone sprays and the 3 mg RiVive are sold over the counter too. Higher-dose sprays, injections and nalmefene need a prescription, and each has its own storage rules.
| Product | Form and dose | Sold | Store at | Worth knowing |
|---|---|---|---|---|
| Narcan | Nasal spray, 4 mg | Over the counter | 36 to 77°F, room temperature or refrigerated | Don’t freeze; keep below 104°F |
| Generic naloxone (Teva and others) | Nasal spray, 4 mg | Over the counter | Below 77°F | Don’t freeze; keep below 104°F |
| RiVive | Nasal spray, 3 mg | Over the counter | 68 to 77°F | Don’t refrigerate |
| Kloxxado | Nasal spray, 8 mg | Prescription | 68 to 77°F, trips 41 to 104°F | Can be thawed and still used |
| Zimhi | Injection, prefilled syringe | Prescription | Below 77°F, trips to 104°F | Replace if the liquid turns yellow or brown |
| Opvee (nalmefene) | Nasal spray | Prescription | 59 to 77°F, trips 39 to 104°F | A different opioid reversal drug |
The differences matter if you keep more than one kind. RiVive, which the FDA approved for over-the-counter sale on July 28, 2023, says not to refrigerate it, unlike Narcan. Zimhi is an injection with a needle, so it’s stored and thrown away like other sharps. Opvee contains nalmefene, a different drug from naloxone, but it’s kept and replaced the same way.
Drugs@FDA lists the generic 4 mg naloxone sprays from Amneal, Padagis and Teva, and Rextovy, as over-the-counter products.
What to do with expired Narcan
Replace it first, then take the expired spray to a drug take-back site or use a mail-back envelope. If neither is available, follow the FDA’s trash method. Don’t flush it.
Naloxone, nalmefene and epinephrine aren’t on the FDA’s list of medicines that may be flushed. For other medicines, the FDA’s first choice is a take-back site or a prepaid mail-back envelope. When neither exists, it says to mix the medicine with something unappealing, such as used coffee grounds or cat litter, seal it in a bag and put it in the trash. The FDA also notes that sprays may come with their own disposal instructions, so check the box or ask a pharmacist.
After a sprayer is used, the prescription Narcan instructions say to put it back in its box and throw it away somewhere children can’t reach it. Zimhi, which has a needle, goes back to a health care provider or an emergency room in its case. Then restock: a used or expired dose leaves a gap.
Tracking naloxone at schools and workplaces
Organizations that stock naloxone need to know where every dose is, when each expires and whether any has been used. A short monthly check and a reminder before each date covers it.
Naloxone is often spread across buildings, vehicles and first aid kits, and doses get used and not replaced. A simple routine:
- List every box: product, dose, lot number, expiration date and location.
- Check monthly that each box is there, sealed and in date, and stored within its temperature range.
- Restock right after any use, and order replacements before the oldest date.
AED Log’s Narcan and naloxone tracking records each station’s form, concentration, lot and expiration with every dose tracked separately, runs the monthly check, and alerts the people responsible before anything expires. It’s an add-on at $8 per unit per year. Epinephrine works the same way; see our guide to EpiPen expiration.
Narcan expiration FAQ
How long is Narcan good for?
Narcan made since January 2024 has a 4-year shelf life; older boxes had 3 years. Go by the expiration date printed on the box and each blister, as the FDA advises.
Can you use expired Narcan?
The FDA says to follow the expiration date printed on each package, and its general advice is not to use expired medicine. Replace naloxone before it expires, keep a spare, and call 911 for any suspected overdose.
Can Narcan be refrigerated?
Yes. The over-the-counter Narcan label allows 36 to 77°F, at room temperature or in the refrigerator. Don’t freeze it. Other products differ: RiVive’s label says not to refrigerate it.
Can you keep Narcan in a car?
Not for long. The label says to keep Narcan below 104°F and not to let it freeze, and a car can pass both limits. Frozen Narcan won’t spray until it thaws.
How do you dispose of expired Narcan?
Don’t flush it. Use a drug take-back site or a mail-back envelope. If neither is available, the FDA says to mix medicine with used coffee grounds or cat litter, seal it in a bag and put it in the trash.