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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  • My son died March 21,2019, from a terrible episode with Acetal fentenual. This is strong than the regular fentenual. Please get help with your addiction , your playing with a loaded pistol. This was his second encounter with fentenual and it took his life. He was only 26 years old,almost turning 27. He was our baby son, my old son is a heroin addict also. My wife and I , our lives will never be the same. Don’t mess with heroin, it’s a loaded gun.

  • And why has fentanyl become more common than actual heroin? Because of our backward draconian drug laws! Prohibition has never nor will ever work.

    • Man I’m truly sorry for your loss.. I’m willing to bet like alot of the good ones I’ve known to pass the very same way that he was the light in the room if he wanted to be. this comment is equally for the people that will read it as is for you sir.. Just bc someone may have a vice in this life doesn’t mean they are all bad people.. that is a common misconception now a days.. we are people like everyone else… I’m not vouching for every drug abusing addict nor am I trying to justify the actions they take but my point is some good people get involved in things they never should and they get completely lost in the lifestyle.. really they are just like everyone else bc they get high don’t mean deep down they don’t want help and to have things go back how they were.. none of us are perfect but I believe if we only knew how much we hurt the ones we love when we leave them behind we would think twice before we go chasing a stupid high.. The last thing on his mind I’m sure was hurting his loved ones but unfortunately we are not guaranteed a 2nd go around. I hope his story spreads awareness and his name saves guys his age in the future from making the same fatal mistake.. in that way he could still do some good for people but through his uncle…

    • I am so, so sorry for your loss. Please know that many people care and will be praying for your nephew and family.

  • When going through withdrawals I pray to die because this is the worst feeling in the world. I use to ride bulls in the rodeos and they never hurt me like withdrawal.

    • Don’t pray to die as God is a God of the living. OK know this. The Greek word for pharmaceutical is sorcery. Sorcery in the Bible is linked to the spiritual warfare we face on earth. I’ve quit cannabis which is a massive aid for satins Kingdom against humanity. I pray this for you. Lord jesus lead this man out of darkness of a agent of satin and into the light of God. Satin knows if you know the truth it will set you free. Knowledge.

    • I detoxed cold Turkey off of the 75mcg/hr Fentanyl patches after being kicked out of a pain clinic because a blood test showed I had no Fentanyl even though I had a patch on when I took the drug test & I literally had a fentanyl patch on 24/7 375 days a year for 3 years & 8 months not one day without wearing a patch & one blood does says there’s no fentanyl in my system & that’s it they basically said see ya go ahead and deal with detoxing on your own off of 75mcg/hr Fentanyl and 20 mg A-day of a day of Opana & zanaflex & xanax. And guess what I learned first hand & what I found out… it’s really easy the detox off of opiates cold turkey if you use marijuana as the treatment just for the withdraws of course. Opiate free since November 2016. Also been in constant pain since November 2016.

    • Trent,
      Don’t pray to die. You’ve already been sick. Go to detox. You will feel better. DO IT

  • Too bad the response to this problem was not only misguided, but led to a lot of unnecessary deaths. This problem is only going to get worse, until they start applying facts and science to the problem. This was created by our current healthcare system, and the American Epidemic Of Despair. The CDC and the FDA have industry insiders in charge who decided to profit from this instead of treating it like a public health issue. The Fact that the suicide rate keeps going up could indicate some problems, instead they are still in denial. The media spread lies, hysteria and misinformation about this topic while the drug cartels took advantage of the unscientific and ridiculous response.

  • Are you talking about Carfentanil (the illegal synthetic fentanyl also known as elephant fentanyl) or are you talking about prescription fentanyl?
    These are completely different and you are providing misleading information.

  • The Worst Opioid you can take is Norco or HydrocodoneAPAP. The Tylenol in it will have you in agony Before you die!! Tylenol should be sued and taken off the market. Lots of ppl who drink take it the next day for hangovers , and end up dying because of it. No one reads that damn bottle.

    • Hydrocodone is a pain reliever, not a hangover cure. If people are stupid enough to take an over the counter narcotic because they drank too much, they deserve that chance of leaving the gene pool.

    • 90-300mg is typically classed as an overdose.
      But 15-30mg is a typical “hit” and has been known to lead to fatalities.
      Article is fine.

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