Opvee (Nalmefene) vs. Narcan (Naloxone) – The Differences & What You Need to Know

Lately, we’ve been hearing more about Opvee (nalmefene) as another option for reversing opioid overdoses. While it works similarly to Narcan (naloxone) by blocking opioid receptors & restoring breathing, there are some important differences—& some serious concerns that has the public health community talking. We talked about this yesterday with higher dose naloxone formulations- but there are other medications coming out, too. One is Opvee- a formulation of nalmefene in a nasal spray, similar to Narcan.

What Makes Opvee Different?

  • Lasts Longer – Opvee stays in the body for up to 11 hours, compared to Narcan’s 30–90 minutes. (Source: Medical News Today)
  • Much Stronger – It has a more powerful effect, which can make withdrawal symptoms way more intense & sudden. (Source: Opvee Official Site)
  • Not Widely Available & Cost Prohibitive – Narcan is affordable & easy to get, while Opvee is expensive & not stocked in most community programs.

Now, you maybe thinking why these things maybe bad- however, to understand why, we must first understand what Narcan does.

Opioids (like fentanyl, heroin, & oxycodone for example) work by attaching to the opioid receptors in our brain, kind of like how a Velcro strip sticks to fabric. When opioids latch on, they slow breathing &, in high enough amounts, can completely stop it, leading to an OD.

That’s where Narcan (naloxone) comes in. Narcan is like a stronger, stickier Velcro that kicks opioids off the receptors & blocks them from reattaching. This quickly restores normal breathing & wakes the person up. But because Narcan only lasts 30–90 minutes, & some opioids stay in the system much longer, a second dose may be needed until medical help arrives.

This is also why people that are dependent/addicted to opioids might wake up feeling horrible & in withdrawal—Narcan shoves all the opioids away at once, causing sudden withdrawal symptoms like nausea, chills, & body aches. It’s unpleasant, but it saves lives.

Now, back to Opvee- because it lasts longer & is much stronger, this makes the withdrawals a patient experiences MUCH worse, & they last longer too. This, in turn, has the potential to cause people to possibly not call for help. They also may try to use a lot of opioids after being revived, hoping to get rid of the withdrawal- but this puts them back into OD territory.

Why Isn’t Opvee Recommended?
OD reversal is about restoring breathing without causing unnecessary harm. Narcan does this safely, while Opvee’s strength & long duration could actually make things worse by triggering dangerous withdrawal symptoms.
Source

Bottom line? Stick with Narcan unless a medical provider tells you otherwise. It’s safer, easier to use, & the best tool we have right now to save lives.

Where to Get Narcan in Maryland?

  • Amazon & retail pharmacies carry Narcan, & you can get it there. You do not need prescription for Narcan in Maryland.

You can get Narcan for FREE here:

  • Maryland Dept. of Health – Find local naloxone providers:
  • NEXT Distro – Free Narcan by mail in Maryland:
  • Local Health Departments – Many offer free Narcan and training.

If you have questions, ready to get off opioids, need Narcan, or just want to talk, please reach out. You’re not alone💙