The Trimbos Institute in Holland has issued a warning about pink 'Superman' pills.
One of the test centres of the Drugs Information and Monitoring System (DIMS) received a pill last week, where it was tested and found to contain a high dose of PMMA (Paramethoxymethamphetamine).
Saying the pill, being sold as ecstasy, is stamped with the Superman logo on both sides, the Trimbos page explains: "The difference between MDMA and PMMA is that the effects of PMMA occur much later, by which time the user may have an illusion of a low dose of MDMA.
"Hours after a dose of PMMA is ingested, severe physical effects such as increased heart rate and extremely elevated body temperature may suddenly occur."
With the Amsterdam Dance Event (ADE) taking place this weekend, Trimbos is strictly warning people to not take this pill.
Last year, UK police seized 400 pills similar to the one described by Trimbos after they were linked to four deaths in Suffolk and Shropshire.
Read about our campaign on safe ecstasy use here.
See warning poster up in Amsterdam below.
Dave Turner is Mixmag's Digital News Editor, follow him on Twitter