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A fentanyl future?

David Nutt      

2nd August 2017

Today’s report of over 60 deaths last year in which fentanyl was implicated raises major alarm bells in the opioid treatment community. It could be the prelude to a wave of deaths from this synthetic opioid (as is now being seen in the USA), where now most street “heroin” is boosted with fentanyl. So what can, and should, we do about it?

First we need to understand what fentanyl is. It’s a highly potent synthetic opioid that has the same pharmacology as morphine and heroin but is chemically synthesised rather than being made from the opium poppy. It’s an old drug having been invented in the 1960s as an alternative to morphine in the treatment for pain in surgery, and more recently developed as a pain killer that is administered via skin patches or slow IV infusions to people after operations.

Being synthetic, fentanyl production is not subject to the vagaries of opium growing and so is more reliably available. Attacks on opium poppy production as part of the “war on drugs” have on occasions led to critically low supplies of morphine, so fentanyl can readily take its place. It’s this chemical synthesis of fentanyl that has led to its rise as a heroin alternative. Fentanyl is significantly cheaper to obtain than heroin as it can be made in a few steps from readily available chemicals. Even more worryingly, precursors that require just a one-step transformation into fentanyl are legally available.

So why is fentanyl a problem? In addition to its relative ease of production, fentanyl is much more potent than heroin, at least 100x more. So the therapeutic dose is of the order of 50 micrograms whereas for heroin its 5 milligrams. This means that overdosing on fentanyl is very much easier than on heroin – pictured below are fatal doses for heroin and fentanyl. Measuring out consistent doses of fentanyl is difficult due to the low weights so errors will be made leading to accidental overdose, and mixing it with heroin will add to the risk as their effects to stop breathing will be additive.

Comparing fatal doses of heroin and fentanyl

What needs to be done? I suggest a six-pronged approach.

  1. Open supervised injection rooms in all localities, so that if someone has inadvertently been sold fentanyl and collapses after dosing they can be immediately resuscitated
  2. Make the antidote naloxone readily available from all pharmacies on request, and expand the education package as to how to use it
  3. Re-invigorate addiction treatment services that use opioid substitution approaches i.e. methadone and buprenorphine, to heroin addiction. The current political obsession with abstinence-based approaches to addiction is leading to more overdose deaths
  4. Stop the destruction of the UK psychiatry addiction services; the past decade has seen over half of all addiction psychiatrist made redundant as services move into the private sector. We need to train more such expert physicians not eliminate them
  5. Invest in research on opioid addiction. Currently the Medical Research Council is not supporting any research projects in heroin addiction, having closed their only two last year. We need to resurrect this critical area of research to allow us to understand the brain mechanisms of addiction, optimise current treatment approaches and develop new ones that will allow people who use opioids to eventually come off them and be protected from relapse.
  6. Ban all close precursors of fentanyl

And also be aware that even more potent synthetic opioids such as carfentanil exist and these are beginning to appear in the USA black market, so we must act now in the UK.


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