Three men remained in intensive care this morning after taking a substance "misrepresented" as MDMA in Hawke's Bay.
A fourth was also admitted to Hawke’s Bay Fallen Soldiers' Memorial Hospital on Monday afternoon.
Dangerous drug warning website High Alert issued a notification about the substance yesterday, warning of "serious harm".
"The effects after consumption are not consistent with typical MDMA use," the notification said.
"A sample was provided and preliminary testing showed it to contain dimethylpentylone, a synthetic cathinone.
"It's not currently known how widely this substance is circulating, or what other substances may be found in the sample."
An overdose of dimethylpentylone can cause death, High Alert added.
"Other synthetic cathinones have lower active doses than MDMA – meaning people may unexpectedly take a larger dose than intended.
"Further analysis is currently being done," the notification said.
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