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W-18: What You Should Know

W-18: What You Should Know

By In Opioid Addiction
Posted November 8, 2016

People willing to profit from the suffering of others are not in short supply. Combine this with the current opioid epidemic, and what’s left is a situation ripe for the introduction of W-18 to our communities.

What is W-18?

What is W-18, and why are we seeing it now? W-18 is currently classified as a synthetic opioid. It is one in a series of 32 substances labeled W-1 through W-32 that were developed together in Canada. W-18 has no known clinical use, and is considered 10,000 times more powerful than morphine and 100 times more potent than fentanyl.

W-15 has also been appearing on the street for illicit use, but is not seen as frequently as W-18. Both are causing major concerns in the recovery community, local hospitals, and law enforcement offices.

Classification of W-18

W-18 was invented at the University of Alberta by a lab working on pain relievers in the 1980s, and it had shown promise as a pain killer in mice. But the synthetic opioid was later determined not to be viable for further work. The chemical has since been found mixed with other chemicals for recreational drug use as substitute for other controlled substances, such as OxyContin and heroin.

“W-18 itself was originally believed to be an opioid, but later it was determined to not properly fit that category due to weak activity at both sigma receptors and the translocator protein (peripheral benzodiazepine receptor). It also inhibits hERG binding, an important antitarget in drug discovery, which possibly causes cardiovascular side-effects.” [1]

Although devoid of opioid receptor activity, weak activity of W-18 at the peripheral benzodiazepine receptor was found and the drugs appear to exhibit toxicity in HEK cells (human embryonic kidney cells) with overnight incubation at concentrations higher than 1 micrometer. However, it is still classified as an opioid. Sounds confusing, right? Let’s unpack this a little more.

Misconceptions about Reversing W-18 Effects

What does all this mean to someone suffering from substance use disorders? Since W-18 is thought to fall into the opioid class of drugs, many who abuse it may falsely believe the effects can be reversed with naloxone, much like we commonly see for heroin, fentanyl and other opioids. Given the lack of apparent activity at opioid receptors, the use of naloxone and other opioid antagonists in treating over-dose is unlikely to be effective and an overdose of W-18 in not likely to be reversed successfully.

Knowing this, many users have elected to smoke the chemical, believing they are not going to experience the overdoses seen from IV use. However, there are several problems with this line of thinking.

First, as noted earlier, there are indications that W-18 has adverse effects on the heart and can lead to additional complications beyond the very high risk of overdose. Among these complications are irreversible heart damage and brain damage.

Secondly, the potency of any given batch of W-18, even when pressed into bootleg pills (commonly called “Shady 80s” on the street), varies greatly. Users can never be certain of what they are getting, which leads to an increased risk of overdose from other forms of administration (including snorting or smoking).

An Uncontrolled Mixture

One sampling confiscated in Canada found that some W-18 pills were near full strength while others had no trace of the synthetic opioid at all. There are no industry standards or watchdog groups overseeing this mixing process. These are criminals mixing the compounds, not pharmacologists. And quite frankly, these people only care about getting more money – even if it means killing people along the way.

Why are People Using W-18?

Given this information, why would anyone take the chance of using W-18? Only certain labs can test for W-18, so users may be trying to avoid detection. Perhaps they have to report to a probation officer or drug court. Or they may be enrolled in a treatment program that does UA testing.

There’s also a chance the drug is being mixed into illegal doses of fentanyl, either intentionally or otherwise. So, in some cases, the user may not even be aware he or she is being exposed to W-18.

No matter the source or the user’s intentions, the dangers and risks of W-18 remain very high, and we are likely to see increased hospitalizations and deaths as a result of the supply flooding our streets.

1. Huang, Xi-Ping; Che, Tao; Mangano, Thomas; Rouzic, Valerie Le; Pan, Ying-Xian; Majumdar, Susruta; Cameron, Michael; Bauman, Michael; Pasternak, Gavril; Roth, Bryan L. (24 July 2016). “Pharmacology of W-18 and W-15”.bioRxiv. doi:10.1101/065623.

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