Local health authorities are raising concern about high-dose MDMA circulating in the community.
The drugs, commonly known as ecstacy, have been seized by NSW Police who say they contain more than two times the average dose of MDMA per tablet.
The high doses have been found in a purple-grey tablet with a punisher skull design on the front.
They can cause severe agitation, raised body temperature, seizures or fits, irregular heart rhythm and death.