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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  • this posting software is not good. i wrote this comment dec 2 but the software does’t due a continuous thread. it sends you another page for older comments. anyway…

    Neither Republicans nor Democrats have the guts to fix the drug situation once and for all. It is easy to fix and will generate millions of jobs, grow the economy, reduce the US debt, diminish the dual underground economy, destroy the cartels, change urban culture, decrease dependency on welfare and update people’s outdated views on addiction while making America great again without Trumps help. How?

    Just like Nancy Reagan meant to say, “Say Yes to Drugs!” Legalize all drugs with the drinking age. Drug manufacturing is regulated, open to start ups and pharmas. Legal recreational drugs must past same quality requirements we expect of prescription drugs. Towns cannot override national legalization. Drugs can and should be taxed at the national, state and local levels provided the pricing does not discriminate lower income groups ability to purchase them which would cause the reemergence of underground drug economy with cheap prices enticing cartels to come back. This is important.

    Next is reallocating the billions of our dollars spent by the DEA/FBI/CIA/Police etc in the failed war on drugs and putting it towards alcoholism & addiction research and mental illness research to cure addiction and control substance or alcohol abuse for once and for all. This means we will need more scientists and healthcare professionals.

    Funds will be used too for opening drug treatment centers and drug enjoyment centers which provide a monitored and safe environment much like casino’s do for gamblers. These enjoyment centers are like Morocco opium dens in the 30’s. You have a safe and protected place staffed by health professionals in which you can partake of drugs that produce a dream state or an acid trip. Free needles etc.

    Lastly, 90% of prisoners are incarcerated for non violent drug crimes. Releasing these prisons immediately reduces national and state wide operating expenses and frees our court system to once again focus on real crimes with a true right to speedy trial. the private prison operators will fight this. We won’t need them anymore!

    We have a right to bear arms. we should also have a right to drink alcohol and/or ingest drugs. Legalizing drugs will prohibit urban males and females from being attracted to the drug money as it will no longer exist. Instead, it will hopefully push them towards a career in healthcare working in these centers.

    And in the end this will make a significant impact on reducing our national trillion dollar debt and improve our society. Portugal made the first step showing it is the solution. Time for america to show the world! Real change takes real action, not fake news like, “Just say No to drugs.” Ya, right.

    I posted similar idea in november at https://www.bostonglobe.com/metro/2017/11/30/more-than-drug-cases-dismissed-after-misconduct-chemist-and-former-prosecutors/C9cWcNDn34axTv8mXRLB9O/story.html#comments

    “Resist much, obey little”
    Once unquestioning obedience, once fully enslaved;
    Once fully enslaved, no nation, state, city, of this earth,
    ever afterward resumes its liberty. – Walt Whitman

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