The US is in the midst of a healthcare epidemic. Tens of thousands of people are dying each year from opioid drugs, including overdoses from prescription painkillers such as OxiContin (oxycodone) and the illicit street drug heroin, and each year the numbers rise.

The opioid epidemic is currently killing almost twice as many people as shootings or motor vehicle accidents, with overdoses quadrupling since 1999. According to Gary Franklin, medical director of the Washington State Department of Labour and Industries and a professor of health at the University of Washington, the opioid epidemic is ‘the worst man-made epidemic in modern medical history in the US’.

 Montgomery Ohio

Montgomery, Ohio, is at the centre of the epidemic, with the most opioid-related deaths per capita this year. Image: Wikimedia Commons

Incredibly, an influx of synthetic opioids is making the problem worse. Fentanyl, a licensed drug to treat severe pain, is increasingly turning up on the street as illicit fentanyl, often mixed with heroin. According to the NCHS, fentanyl and synthetic opioids are blamed for 20,145 of the 64,070 overdose deaths in 2016. Heroin contributed to 15,446 deaths, while prescription opioids caused 14,427.


Potent opioid

Fentanyl (C22H28N20), a lipophilic phenylpiperidine opioid agonist, is generally formulated as a transdermal patch, lollipop and dissolving tablet. Like the opioids derived from opium poppies, such as morphine, fentanyl binds to opioid receptors in the brain and other organs of the body, specifically the mu-receptor.

 opium poppy

Heroin and other opioids come from the opium poppy.  Image: Max Pixel

Such binding mimics the effects of endogenous opiates (endorphins), creating an analgesic effect, as well as a sense of well-being when the chemical binds to receptors in the rewards region in the brain. Drowsiness and respiratory depression are other effects, which can lead to death from an overdose.


Rise of illicit fentanyl

The opioid epidemic can be traced back to the 1990s when pharmaceutical companies began producing a new range of opioid painkillers, including oxycodone, touting them as less prone to abuse. In addition, prescribing rules were relaxed, while advocates championed the right to freedom from pain. Soon, opioids were being prescribed at alarming rates and increasing numbers of patients were becoming hooked.

 

Why is there an opioid crisis? Video: SciShow

Franklin, who was the first person to report in 2006 on the growing death rate from prescribed opioids, says: ‘OxyContin is only a few atoms different to heroin – I call it pharmaceutical heroin.’

A crackdown on prescribing was inevitable. But then, with a shortage of prescription opioids, addicts turned to illicit – and cheaper – heroin. According to Franklin, 60% of heroin users became addicted via a prescribed opioid. ‘You don’t have to take these drugs for very long before it’s very hard to get off,’ he says: ‘Just days to weeks.’ Heroin use soared and with it increased tolerance, leading users to seek out more potent highs. By 2013, there were almost 2m Americans struggling with an opioid-use disorder.


Drugs to fight drugs

 public health emergency

President Trump declared the opioid crisis a public health emergency in October. Image: Pixabay 

Attention is finally being given to the epidemic. US president Donald Trump recently declared a public health emergency, although no new funds will be assigned to deal with the crisis.

There is particular interest around research into a vaccine against fentanyl. Developed by Kim Janda at The Scripps Research Institute, California, US, the vaccine, which has only been tested in rodents, can protect against six different fentanyl analogues, even at lethal doses. ‘What we see with the epidemic, is the need to find alternatives that can work in conjunction with what is used right now,’ he says.

This vaccine could treat heroin addiction. Video: Seeker

The vaccine works by taking advantage of the body’s immune system to block fentanyl from reaching the brain. Its magic ingredient is a molecule that mimics fentanyl’s core structure, meaning the vaccine trains the immune system to recognise the drug and produce antibodies in its presence. These antibodies bind to fentanyl when someone takes the drug, which stops it from reaching the brain and creating the ‘high’.