he opioid crisis just keeps getting worse, in part because new types of drugs keep finding their way onto the streets. Fentanyl, heroin’s synthetic cousin, is among the worst offenders.

It’s deadly because it’s so much stronger than heroin, as shown by the photograph above, which was taken at the New Hampshire State Police Forensic Laboratory. On the left is a lethal dose of heroin, equivalent to about 30 milligrams; on the right is a 3-milligram dose of fentanyl, enough to kill an average-sized adult male.

Fentanyl, according to the Centers for Disease Control and Prevention, is up to 100 times more potent than morphine and many times that of heroin.


Drugs users generally don’t know when their heroin is laced with fentanyl, so when they inject their usual quantity of heroin, they can inadvertently take a deadly dose of the substance. In addition, while dealers try to include fentanyl to improve potency, their measuring equipment usually isn’t fine-tuned enough to ensure they stay below the levels that could cause users to overdose. Plus, the fentanyl sold on the street is almost always made in a clandestine lab; it is less pure than the pharmaceutical version and thus its effect on the body can be more unpredictable.

Heroin and fentanyl look identical, and with drugs purchased on the street, “you don’t know what you’re taking,” Tim Pifer, the director of the New Hampshire State Police Forensic Laboratory, told STAT in an interview. “You’re injecting yourself with a loaded gun.”

New Hampshire, like the rest of New England, has been particularly hard hit by the opioid epidemic. The state saw a total of 439 drug overdoses in 2015; most were related to opioids, and about 70 percent of these opioid-related deaths involved fentanyl. The state has seen 200 deadly opioid overdoses this year so far, said Pifer.

Fentanyl was originally used as an anesthetic. Then doctors realized how effective it was at relieving pain in small quantities and started using it for that purpose. In the hands of trained professionals — and with laboratory-grade equipment — fentanyl actually has a pretty wide therapeutic index, or range within which the drug is both effective and safe.

The difference in strength between heroin and fentanyl arises from differences in their chemical structures. The chemicals in both bind to the mu opioid receptor in the brain. But fentanyl gets there faster than morphine — the almost-instantaneous byproduct when the body breaks down heroin — because it more easily passes through the fat that is plentiful in the brain. Fentanyl also hugs the receptor so tightly that a tiny amount is enough to start the molecular chain of events that instigates opioids’ effects on the body.


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This tighter affinity for the opioid receptor also means more naloxone — or Narcan — may be needed to combat a fentanyl overdose than a heroin overdose.

“In a fentanyl overdose, you may not be able to totally revive the person with the Narcan dose you have,” said Scott Lukas, director of the Behavioral Psychopharmacology Research Laboratory at McLean Hospital in Belmont, Mass. “Naloxone easily knocks morphine off of the receptor, but does that less so to fentanyl.”

Matt Ganem, a former addict, explains the excruciating process of opioid withdrawal. Alex Hogan/STAT

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  • Boscoe I kind of agree ,why pick up a new drug addiction to overcome another drug addiction. As its proven Rehab expecially the useless 28 day program does not work. After a few trys only 2 % stay clean for 6 months .
    They eventually go back to useing. But it’s the states easy way out to deal with the opioid crisis. I could almost swear the state of NH. wants the addicts to die off to rid of this epidemic. I hear this from many addicts 5 to 6 day’s a week. Boscoe its a vicious cycle if you don’t stop you will die or be brain dead and, shorten your life span. I’ve worked many years with addicts. If we don’t put them somewhere for a long time, this addiction is spreading. In another 20 years there will be more kids on drugs than that are off drugs. You only hear the botched 500 a year drug deaths. not the complications from drug deaths (infected heart valve exp.) The overdoses per year in any one city in NH. is in the thousands, per city. Thanks to Narcan and fire/ emt. Too bring them back to life. Meth puts holes in their brains and lungs. A hospital stay is then needed. We soon in years will be a third world country full of strung out zombies, as new and stronger drugs are hitting streets. Wait until Flakka hits NH. They eat people alive. I’ve seen it in Fla. Drugs are the closest thing to he’ll on earth. Flakka is pure evil. They feel no pain, they are predators, they crave the taste of blood, they think they have super powers, running into moving cars and, they don’t die.

  • Ayesha I don’t want to be suboxone or anything I went to see Cecilia stone I overdosed the China she did nothing probation don’t care why I want quit

  • Yes 99 out of the 100 random tested had Hep C . As we know a 28 day rehab only works after several trys. If the person really wants to quit. We have a young lady in the system that completed the 28 day rehab 11 times. she’s still useing. Our rehabilitation is not successful. Not long enough. Just facts, all users say rehab. The easy way out. I’ve seen the best success with locking the kids up for 10 years. lots came out good productive citizens. except our prisons are full.
    Carrie please go get tested.

  • 99% of drug users do not have hepatitis C. I do not know what kind of study you conducted, but it clearly wasn’t randomized or able to be generalized to the IV drug user population. Furthermore, I think it is very unfortunate that we are still trying to criminalize every drug user. Throwing people in prison does not solve social problems and chemical dependency has been shown to be more of a disease than simply poor choices. Try to have more empathy, Mr. Browne, and advocate for more rehabilitation not prisons. Children should not be outside barefoot, more so for a host of other reasons such as injury and bacterial infections, not stepping on dirty needles. So yes, still put shoes on children.

  • We took 100 random drug shooters and, tested them. 99 out of 100 tested positive for hepatitis c. 86 tested positive for AIDS, out of 100. New Hampshire if your not going to put them in prison or get them to stop useing. Please give them clean syringes. I’m tired of seeing used needles in our playgrounds and,parks. I wonder how many innocent children/people are getting stuck from these needles and,getting dieases? Don’t let your children out barefoot.

  • That doesn’t have to be your way out of this, Henry. You’re worth it, ya know. Let me help you. Come to the Suboxone talkzone forum online & post in introduction. We will all respond to you. Don’t kill yourself, you’re not a coward. We can get you help.

  • I have been on morphine from the va for 4 years now. They want to just cut me off so a fentanyl is my best bet. Just mic all at once, a for sure thing. Or try and save half in case things don’t go as planned.
    Peace out and no pain.

    • Trey Leech, come to the Suboxone talkzone forum. You can break away from that s*** & begin a buprenorphine program. We can help you!

  • So Henry Leech, does this mean you’re going to kill yourself? I don’t understand what you meant in that statement.

  • Even if right now you see so much darkness in your life that you don’t want to be here anymore, there is always light out there. From personal experience, even at the bottom of the pit, you can always bring yourself to the ladder up. Life is beautiful and you deserve to be happy, love yourself and be loved by others.

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