Three different ecstasy pills containing twice the average amount of MDMA are circulating in NSW, prompting a warning from the health department as the music festival season rolls on.
NSW Health says the pills found recently include a blue diamond-shaped tablet with a Punisher logo; a blue skull-shaped tablet stamped with 'MYBRAND'; and a yellow square tablet branded with the character Spongebob.
The latter was found to contain 160 milligrams of MDMA, while the former two contained 216 milligrams.
The health department says MDMA tablets and capsules have also been found to contain other substances, including ketamine, ketamine analogues and cathinones, which are chemically similar to amphetamines.
The latest warning follows another issued in late September about high-dose pink pills bearing a Gucci logo.
NSW Poisons Information Centre medical director Dr Darren Roberts said high doses of MDMA were linked with recent cases of serious illness and death.
"MDMA can cause severe agitation, raised body temperature, seizures or fits, irregular heart rhythm and death," Dr Roberts said.
"The amount of MDMA in a tablet or capsule can vary a lot, even within the same batch.
"The health risks from MDMA are greatly increased if high amounts (including multiple doses) are consumed over a short period."
Hot environments, such as music festivals, increased the risk of harm, he said, advising that people should take breaks, seek shade, and drink water.
Dr Roberts said combining MDMA with other stimulants like cathinones, cocaine and amphetamines was also risky.
He urged people to call triple-0 if they or a friend felt unwell after taking drugs, explaining they would not get in trouble.
"There are teams of well-trained peer volunteers from programs such as DanceWize NSW and medical providers who are ready to support you at many major festivals," Dr Roberts said.
"Other event staff are also trained to help patrons."
Two men died in suspected drug-related incidents in late September after attending the Knockout Outdoor music festival in Sydney, while several others who attended festivals that same weekend were taken to hospital.
A man has been charged with supplying a drug in relation to one of the deaths; his case remains before the courts.
Health Minister and Keira MP Ryan Park said the government had no plans to introduce the measure, but was "not closing the door on reform".
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