Electronic vaping devices (e-cigarettes or ‘vapes’) have become more common in recent years. Initially introduced to help people stop smoking tobacco. However, there have been increasing concerns and criticisms of their availability because they often come in flavours and packaging that may appeal to young people.
In the UK, we’ve also seen a rise in illegal “cannabis” vape products. These products are often not what they seem, and they can be dangerous.
What are Illegal ‘Cannabis’ Vapes?
Vaping is a way some people are now consuming cannabis. Cannabis in the UK is only legal when prescribed for individual patients. Illicit cannabis does not go through the same quality control processes as medical cannabis and, as such, might contain harmful substances.
Many disposable vapes, e-liquids, and products claiming to contain tetrahydrocannabinol (THC), one of the main active compounds in cannabis, have been found to contain something called “synthetic cannabinoid receptor agonists.” These are man-made chemicals that can be harmful.
A recent observational case series described the cases of seven patients admitted to two hospitals in the UK who said they had used vaping products. Tests showed they had been exposed to MDMB-4en-PINACA, a synthetic cannabinoid.
What is MDMB-4en-PINACA?
MDMB-4en-PINACA is a strong, man-made chemical that acts like cannabis in the body. It was first found in Europe in 2017 and was flagged as a new concerning substance in 2018. In 2021, it was the most common synthetic cannabinoid found by the Drug Enforcement Administration in the United States.
Using too much of this chemical has been linked to various unwanted effects, including seeing or hearing things that aren’t there (psychotic symptoms) and death.
MDMB-4en-PINACA Detected in Illegal Cannabis Vapes in the UK
The recent study found seven patients in hospital between February 2022 and February 2025 who were exposed to MDMB-4en-PINACA through a vaping device. Four of these patients said they were vaping THC, one said they were vaping CBD, and two just said they were “vaping” other products before they felt unwell.
All of these patients experienced unwanted effects:
- Five patients showed “unusual changes in behaviour.”
- One patient collapsed and was admitted to the hospital.
- Another patient had a seizure.
- Six patients were agitated when they arrived at the hospital, and four needed medication to calm them down.
- Four patients experienced psychotic symptoms, like hallucinations and believing things that weren’t true.
- Five patients were seen by a mental health team during their hospital stay, and two were later admitted to a psychiatric hospital.
Only one patient’s vape product was available for testing. This test found MDMB-4en-PINACA in the vape, and it was also found in the patient’s urine 11 days later.
Urine samples were tested for the other six patients:
- In three cases, MDMB-4en-PINACA was the only substance found.
- In two cases, cannabis was also detected.
- In one sample, other synthetic cannabinoids were found.
Cases of Synthetic Cannabinoids on the Rise
Recently, there have been more reports of synthetic cannabinoids, like MDMB-4en-PINACA, being found in e-liquids and vapes. But there aren’t many official reports that describe how patients are affected by these chemicals, especially with lab tests to confirm it.
In the UK, two deaths between 1997 and 2020 have been linked to vaping synthetic cannabinoids. Both of these deaths were male prisoners. In the recent study, most of the patients were young people, and none of them said they intentionally used synthetic cannabinoids. Many patients experienced symptoms for a long time, with the average hospital stay being 37 hours.
What This Means for Healthcare
The authors of this study noted that none of the patients had a mental health diagnosis before this. Because of this, they suggest that if young patients show mental health symptoms, especially for the first time, doctors should ask about vaping and think about testing for synthetic cannabinoids.
Protecting Cannabis Consumers
Illegal cannabis vapes are becoming more common on the UK black market. However, many of these products might not be labelled correctly, as previous studies have shown. When these products are contaminated with other substances, like synthetic cannabinoids, it can be a risk to public health. It’s very important to help people, especially young people, understand the possible dangers of these products.
