Carfentanil: The next step in the opioid crisis?

The US is in the midst of a national opioid epidemic. The use of opioids, which includes prescription drugs and heroin, has quadrupled since 1999. The Centres for Disease Control and Prevention (CDC) has confirmed that these drugs now kill more people than car accidents in the US, making it the most common form of preventable death.

Opioids are a class of opium-derived compounds that relieve pain. These drugs use the same receptors as endorphins, eliciting analgesic effects by inhibiting the release of neurotransmitters in the spinal cord. Exploited for centuries, they are still considered one of the most efficacious treatments for pain, despite serious side effects including physical and psychological addiction.

Fentanyl, a synthetic opioid developed for use in surgery, was first linked with overdose deaths in 2005 . Alarmingly, the number of overdose cases involving fentanyl have escalated in recent years, with its misuse regularly making the headlines due the sheer number of deaths associated with this drug. High profile cases, such as the death of the global star Prince have only added to this.

Carfentanil, another drug with a similar structure to fentanyl, has recently exploded onto the scene as carfentanil-laced drugs rear their toxic heads. An analogue of fentanyl, carfentanyl was first synthesised in the US in 1974 by Janssen Pharmaceutica (owned by Johnson & Johnson). This opiate was designed for use as a general anaesthetic in large animals such as rhinos – just 2mg of carfentanil can knock out an African elephant. Due to its extreme potency the lethal dose range of this drug is unknown in humans, which greatly amplifies the risk involved in taking the drug.  Carfentanil is 10,000 times more potent than morphine, and 100 times more potent than fentanyl. As with other opioids, carfentanil causes death by respiratory distress or cardiac arrest, leading to death within minutes.

So, why are these drugs being increasingly abused? One explanation is that prescription of opioid drugs have increased since the 1970s – this being the result of a series of papers published downplaying the risk of addiction associated with use of opioid painkillers such as oxycontin and fentanyl. They were marketed to doctors as wonder drugs for treating day-to-day pain, with little addiction potential. As we now know, this turned out not to be the case. The resulting willingness of doctors to prescribe opioid painkillers increased the availability of these drugs. This problem was in turn worsened by a subset of pharmacies illegally filling out multiple prescriptions and the phenomenon of ‘doctor shopping’, where patients obtain prescriptions from multiple doctors at once. Currently, over 650,000 new opioid prescriptions are dispensed every day in the US by doctors.

A number of recent studies found that almost half of young people using heroin had abused prescription opioids beforehand. This comes as no surprise when such potent drugs are used routinely to treat even minor sports injuries in young people. As a result of this alarming trend, new regulations were implemented in the US in 2014 to attempt to restrict the misuse of prescription painkillers. Unfortunately, this has forced many people experiencing drug addiction to turn to prescription fraud and illegally produced pills. Cartels in Mexico, the primary supplier of heroin to the US, have stepped in to provide cheaper and more potent opiate alternatives. Evidently, the reduction in the availability of legally-produced drugs has failed to remedy the issue of opioid misuse.

The unknown quantity and composition of the drugs bought on the street, combined with the recent explosion in recreational use, has led to a surge in accidental overdoses. In 2016, both fentanyl and carfentanil have been found as additives in heroin, cocaine and counterfeit Xanax pills in Florida, Ohio and neighbouring Michigan (including Detroit) among other states. Like any other illicit drug, users have no way of determining the strength or purity of what they have bought to any degree of accuracy.

The latest spike in overdoses has led to the DEA issuing a public health warning, with the Acting Administrator Chuck Rosenberg describing carfentanil as ‘crazy dangerous’ . It is hard to put a figure on the number of cases involving carfentanil as there are issues with obtaining samples and identifying how much was taken, with some facilities also unable to identify the compound in toxicology reports at post mortems.
The opioid antagonist naloxone (sold as Narcan™ nasal spray) also struggles to reverse the effects of fentanyl and carfentanil, with reports of patients needing up to five times the recommended amount of naloxone for a heroin overdose. As a result it can take up to five minutes to revive a patient, an effect that normally takes a matter of seconds, vastly increasing the chance of lasting brain damage and death.

On average, opioid overdoses kill 91 Americans every day. This disturbing figure will continue to rise unless rapid change is seen in both government policy and in society as a whole. There remains no easy solution to opioid problem, and with a single gram of carfentanil able to cause 50,000 fatal overdoses, it seems the situation will only worsen unless dramatic changes are put into effect. Continued research into addiction causes and treatments, coupled with investigation into new medications to treat pain are also necessary for long-term management of this devastating crisis.

Post by: Sarah Lambert


Share This