When someone buys a drug illegally, they cannot be sure exactly what is in it.

More than one in three samples submitted to the Welsh Emerging Drug Identification Service (Wedinos) where the buyer had said what substance they believed they had purchased, contained something other than what they expected. Between April 2025 and March 2026, 36.6% of samples submitted to Wedinos did not contain the expected substance.

These findings illustrate how the illicit drug market is often defined by substitution, where the name, appearance or packaging of a drug may tell us surprisingly little about what is actually inside it.

One of the most concerning findings in the latest Wedinos report is the identification of a new group of synthetic opioids known as “orphine analogues”. Synthetic opioids are chemically produced drugs that can have effects similar to opioids such as morphine and heroin.

Orphine analogues are highly potent types of synthetic opioids, meaning they can have powerful effects at very small doses. That creates a particular risk when someone believes they are taking heroin but is actually consuming a different, potentially more potent substance.

The findings are particularly concerning because orphine analogues were identified alongside veterinary sedatives in samples submitted as heroin. The significance is not necessarily that this particular combination has........

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