Naloxone should be stored at room temperature, away from direct light, and protected from freezing and excessive heat. The recommended range is 36°F to 77°F (2°C to 25°C), with brief temperature spikes up to 104°F (40°C) considered acceptable. Beyond those basics, naloxone is a surprisingly resilient medication, and even imperfect storage is far better than not having it available at all.
Recommended Temperature Range
The FDA-reviewed labeling for naloxone nasal spray specifies storage between 36°F and 77°F, which covers most climate-controlled indoor environments. Temporary excursions up to 104°F won’t damage the product. The two conditions to actively avoid are freezing and sustained heat above 104°F.
A room-temperature closet, a kitchen cabinet away from the stove, or a bedroom nightstand all work well. Avoid windowsills, bathrooms (where humidity and temperature fluctuate), and anywhere near a heat source like a radiator or oven.
Light, Moisture, and Packaging
Naloxone is sensitive to direct light over time, so keep it in its original packaging until you need it. The box and foil pouch that nasal sprays ship in aren’t just for marketing; they block light and reduce moisture exposure. Injectable forms typically come in amber-tinted glass or opaque packaging for the same reason.
There’s no need to refrigerate naloxone. Standard room temperature in a dry, shaded spot is ideal.
Keeping Naloxone in a Car
Many people want to carry naloxone in a vehicle, and for good reason: overdoses don’t happen on a schedule. The challenge is that car interiors can reach extreme temperatures. In summer, a parked car’s cabin can climb well past 104°F, with some studies recording interior temperatures near 175°F (80°C). In winter, an unheated car in a cold climate easily drops below freezing overnight.
Research published in Harm Reduction Journal tested what happens to naloxone under these conditions. Injectable naloxone ampoules exposed to daily freeze-thaw cycles (16 hours at -4°F, then 8 hours at 39°F) and to repeated heat exposure maintained their full drug concentration for at least 28 days. The active ingredient stayed chemically stable in both scenarios. However, after about a week of freeze-thaw cycling, visible white particles formed inside the ampoules, suggesting other ingredients in the solution were being affected even though the naloxone itself was not.
The practical takeaway: naloxone kept in a car for days or even a few weeks will likely still work. But it’s not a permanent storage solution. If you do keep a kit in your vehicle, try to store it in the glove compartment rather than the trunk (which gets hotter in summer), and swap it out regularly with a fresh supply stored indoors. A small insulated pouch can also buffer temperature swings.
What Happens After the Expiration Date
Naloxone carries a shelf life of about 24 to 36 months from manufacture, depending on the product. But expired naloxone doesn’t suddenly become inactive. A study examining naloxone products collected from first responders found that most samples still contained more than 90% of their labeled dose, including some that had been stored for nearly 30 years. Small amounts of a breakdown product were detected in the oldest samples, but always at levels below 1%.
This matters in an emergency. If the only naloxone available is past its printed expiration date, it is still worth using. A slightly reduced dose is far better than no dose at all during an opioid overdose. That said, you should replace expired stock when possible, since you want the highest potency available in a crisis.
Where to Keep It at Home
The goal is balancing two things: quick access during an emergency and safety around children. A high shelf in a hallway closet, the top of a bedroom dresser, or a locked but easily opened medicine cabinet all work. Everyone in the household who might need to use it should know exactly where it is. In an overdose, seconds count, and searching through drawers wastes critical time.
If children are in the home, store naloxone out of their reach, the same way you would any medication. The nasal spray device looks like it could be a toy to a young child. Keep it in its sealed packaging in a consistent, memorable spot and make sure other adults or older family members know the location.
Nasal Spray vs. Injectable Forms
Storage requirements are essentially the same across naloxone formulations. Both nasal sprays and injectable versions need room temperature, protection from light, and avoidance of extreme heat and freezing. The nasal spray has a slight practical advantage for home and vehicle storage: it comes in a sealed, single-use device inside a protective pouch, which naturally shields it from light and moisture without any extra effort on your part.
Injectable naloxone, whether in vials or ampoules, is more vulnerable to physical damage. Glass can crack in freezing conditions or if dropped, so store it somewhere padded or cushioned if you’re keeping it in a bag or car kit.
How to Dispose of Naloxone
If your naloxone is expired and you’ve replaced it, or if a device has been used or damaged, the simplest disposal route is a drug take-back program. Most pharmacies and many police stations accept unused medications year-round, and the DEA hosts periodic national take-back events.
If no take-back option is convenient, you can dispose of naloxone in your household trash. Remove it from the original container, mix it with something unappealing like used coffee grounds, dirt, or cat litter, and seal the mixture in a bag or container before throwing it away. Scratch any personal information off the packaging before discarding it.