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.

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 lost my son to that shit just 16 hours ago, he just turned 30 two months ago! I found Him in His bed face down with the needle still in his hand, I lost my Buddy and it feels like my hearts been ripped out!!!!

  • Was (gradually) put on 100mcg patch for auto-immune pain about a year ago. Began to actively wean down about 6 months ago. …75mcg four months ago, 50mcg two months ago. I’ve been cutting thin patches in half, afraid to ask for 25mcg script in case I cannot handle the withdrawal. The approximately 25mcg I started 4 patches ago is AGONIZING. Why I was never warned about this is beyond me. It’s a serious and silent withdrawal. Nobody sees me get the chills while sweating, constipated then diarrhea by day 3, NO SLEEP yet exhausted, intense “bone pain”, spasms. I’m a professional mother of 3. You’d never know I’m a damn addict because of this junk. I want it out of me!!
    Wishing I invested in therapeutic massage, etc instead. 😔

  • What are signs of a fentanly overdose what does it do to your heart does cause you to have a heart attach

    • Opioids tend to suppress respiration – breathing. During an OD your brain forgets to tell you to breathe. There are other drugs that also tend to suppress breathing, alcohol is one, benzodiazepines are another. It is dangerous to combine these and you are much more likely to OD if you do, because they have a synergistic effect, making that respiratory suppression greater than any one of the substances alone.

  • In CA the dealers were using crude tablet presses to produce fentanyl laced tablets that looked like generic Norco. Now they are imprinting and coloring tablets to look like oxycodone 30mg, which contain fentanyl. A quick internet search will find tablet presses available from, you guessed it, India. Tablet press available on eBay, some manual some automatic. This is sad.

  • Just lost my cousin yesterday to a Fentanyl overdose in his jail cell and his 26 year old son just came out of coma from a Fentanyl overdose on Monday. It is so sad, that this drug unlike others have hit the street and into the hands of the unknown. It is like someone stated “its like aiming and shooting a loaded gun” because it is almost certain someone will overdose and or die from this drug.

    • B+#$@, people want to to get HIGH! THAT WILL NEVER EVER CHANGE! so to blame dealers is totally Ludacris, if this is your thinking than DR’s & pharmacist’s are also to blame cause their are many many more deaths related to legally acquired opiate medication!!! So grow up and smell the flowers people…..

    • In many cases it IS the fault of doctors or pharmacists that people are addicted to prescription opiates.

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