The 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.

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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  • I have been to rehab twice. In my opinion rehab and gettin/staying clean is only possible if the person TRULY wants it, if they are just in agony and dont wanna feel the pain anymore, they will just gi to rehab, get out, and start using again because fuck it.

  • This fetenoyl, herion ,meth must be really addictive. We just setenced a young lady with well over 26 drug / violent charges to a 28 day rehab for the 26 time. Hello rehab does not work. It’s a money maker averaging a thousand dollars a day. Wake up the judges.

    • Rehab is successful majority of the time as the addict or patient is in rehab for 2-3 years with job skills before being released.
      28 days does nothing as Sweden has shown that the person entering rehab has 2-8 problems the patient has to work through to rewire the brain. Very professional and human kind.
      Finland has user safe houses so they can stay safe with clean needles and syringes.
      USA is to focused on the capitalism not human kindness.

  • Understanding the potency of opioids is a daunting area.

    But, I shall digress to a safer (?) medication. Specifically, acetaminophen. Were you aware that it has no therapeutic index? The maximum recommended daily dose is 4 Gm daily. The lowest recognized toxic dose is 5 Gm. Really thin line. Check the E.R. records around the world.

  • No comment attorney Browne. The governor spends more money on his real gold dome . Than he does getting addicts to stop useing. He thinks its his money and his house . Hopefully HE’ll be gone soon. We have put some
    addicts/ dealers in the 28 day rehabilitation more than 15 times. The judges are a joke and the addicts know it. Why they don’t even try to stop. Because theirs no real help and no punishment. By the time the drugs are almost out of their systems the judges release them. I’m tired of hearing it from the family’s of their beloved addicts.

  • Yes they sign up for 28 day rehab their free. They don’t even have to go to rehab. No one checks up on them.
    REHAB IS A GET OUT OF JAIL FREE CARD. might as well be legal. It’s just a slap when your caught.
    Mike are you attorney Browne ?

  • Meth ,fetenoyl, herion is legal in NH. I’ve seen thousands of kids getting arrested more than ten times with it. Or selling it. The longest jail stay I’ve seen is six months.

  • Isn’t this the time where some genius starts a legalization push? Don’t look at the bad effects that drugs have, just legalize it and make any claim you want:

    People will use less
    It ‘cures’ {insert anything here}
    You’ll make money off of it in taxes
    blah, blah….

  • Darren, I have to agree with you. The useless rehabs are just money makers. Only a select few eventually quit, out of 100,000. I’ve worked with them for 30 years starting in the mid west,south, north east. Rehab is a useless money making business. Make the bupin. Over the counter ,affordable. Crime would go down, cartels would loose lots of business. In time There would be a lot less needle use, herion, fetenoyl use. Except the rehabs have the politicians,judges in their pockets. It’s all about money. Illegal drugs is a money maker filling all the fat cats pockets including law enforcement. Bigger courts are needed, more police, more federal money, pay offs, fines, thousands of dollars seized. They like this epidemic.
    Their not thinking of the deaths, soon generations lost to drugs. Ive seen the corruption.

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