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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  • I have to be honest when I lived in Nh. I was arrested 9 times in two years with fetenoyl . Or meth and fetenoyl or herion and fetenyl I had to leave Nh to get help because the nh has no free help judges and courts are jokers and they givr no help only a 28 day rehab setence. I cant pay for it no one checks if i went I believe they want us to die

  • Mk your correct it is mainly a white man’s drug. The spanish, Mexicans , Dominicans mainly are cashing in.
    The Nh. System is letting the whites use and die. They know if they overdose they’ll be let go. Probation lets them use. Judges don’t do anything but a 28 day rehab like joel wrote 26 times in 28 day. that no one makes sure they go or complete. If their caught selling small amounts of fetenoyl or caught with it they get 30 days or less. This is a joke and my friends the users know it. Other countries I know a guy that has been in a six year rehab so far with out a known release date. The dealers overdosed on purpose to avoid being held for 30 days. The judges are idiots. Their wrecking society. Maybe their karma will give each of them a close family member addict. We need trump as Governor. Then he would have a closer look into this insanity in NH. THE capitol city has 6 to 8 overdoses every day. manchester has over 10. West Virginia has more deaths because of all the remote areas , can’t get to save them. Nh. Is a drug den. No one should be proud to live there. Live free and die. Holds true dealers and users are free no long term rehab like 3 to 6 or more year rehabs and the rest Die. Keep doing what your doing Nh. Now 46 percent of your population has an addiction. Wait soon more will be an addict than are not.
    This includes alcohol. Nh sells the most alcohol than the hudge states with millions more people, their more druggies and alcoholics in nh. Live free the druggies or let them die

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