Scientists have warned that a fake substitute for MDMA is circulating in Manchester.
4-Chloromethcathinone, or 4-CMC for short, has been found in both pills and powder form throughout the city.
While the drug has been used to pad out MDMA and other drugs before - it's been found at a much higher concentration recently. With its compounds more similar to methamphetamine, there are concerns for potential side effects including sleeplessness, hallucinations and confusion.
The Manchester Drug Analysis & Knowledge Exchange (MANDRAKE) issued warnings on social media after testing drugs across the city and finding high percentages of 4-CMC across the board.
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The director of MANDRAKE, Dr Oliver Sutcliffe told The Daily Mail: "These compounds are potentially more harmful, but the fact is they're not fully understood therefore people don't really understand what doses of things to take or what happens if they are taken in combination."
UPDATE! Results of continued testing/analysis of samples of concern from the #NTE across the 10 boroughs of Greater Manchester.— MANDRAKE (@MANDRAKE_LAB) August 5, 2021
CAUTION! Significant batch-to-batch variation in content. If unwell seek medical attention. #harmreduction #leadingtheway#savinglives#manchester pic.twitter.com/8dikJEqSRu
"The stuff we found on the recreational market was worrying because it was actually mixed in a tablet with MDMA, and the user would assume that it was MDMA but you don't know how these compounds will react in the body."
"We have been analysing samples over the last 16 months, but we didn't see anything like this before Freedom Day."
There have been a number of drug warnings following the reopening of nightlife on July 19. In July 2 people died and a further 20 were hospitalised after taking blue "Tesla" pills that contained super-strength MDMA.
If you or your friends are feeling unwell after taking drugs this weekend, please seek medical help.
For more information on drug safety and pill-alerts head to The Loop, who have provided a helpful graphic on keeping yourself safe while taking MDMA below.
Megan Townsend is Mixmag's Deputy Digital Editor, follow her on Twitter