This is a guide we hope you never need in the moment — but it's the kind of information that's much more useful learned in advance than looked up while it's happening.
Why fentanyl changed the risk calculation
Fentanyl is a synthetic opioid roughly 50 times more potent than heroin and about 100 times more potent than morphine. That potency means the margin between a dose that produces the intended effect and one that stops someone's breathing is extremely narrow — narrower than with most other opioids. It's also increasingly found mixed into other drugs (counterfeit pills, cocaine, methamphetamine) without the user's knowledge, which is why overdose can happen to people who didn't think they were using an opioid at all.
Recognizing an opioid overdose
The core signs, together, are the pattern to watch for: breathing that's very slow, shallow, or stopped; a person who can't be woken up by shouting or a firm sternum rub; blue or gray lips or fingertips; making choking or gurgling sounds ("death rattle"); and pinpoint pupils. Any one sign alone can have other explanations — the combination, especially slow/stopped breathing plus unresponsiveness, is the emergency.
What to do
- Call 911 immediately. Most states have Good Samaritan laws that protect the caller and the person who overdosed from drug-possession prosecution when someone calls for help — the fear of legal trouble should not be the reason someone doesn't call.
- Give naloxone if you have it, following the product instructions (nasal spray is the most common over-the-counter form). It can be given to someone even if you're not certain opioids are involved — it won't harm someone who doesn't have opioids in their system.
- Keep the person breathing. If they're not breathing normally, rescue breathing or CPR (if trained) matters while waiting for naloxone to take effect and for emergency responders to arrive.
- Stay with them. Naloxone's effects can wear off before the opioid does, especially with fentanyl — repeat doses are often needed, and the person still needs emergency medical evaluation even if they wake up.
What naloxone can't do
Naloxone reverses opioid overdose specifically — it does nothing for overdoses involving only stimulants, alcohol, or benzodiazepines, and mixed-substance overdoses may need more than naloxone alone can fix. It's also short-acting, which is why calling 911 is step one, not an alternative to it.
Getting naloxone
Naloxone (brand name Narcan, among others) is available over the counter at most pharmacies in the U.S. without a prescription, and many health departments and community organizations distribute it free. If you or someone in your household uses opioids in any form — including prescription pills — having it on hand is a harm-reduction basic, not an admission of anything.
If you're looking for treatment that includes medication for opioid use disorder, our directory lets you filter for MAT-offering centers directly.