The heartbroken mother of a 22-year-old man who died after a drug overdose at a NSW music festival has told a coroner "if nothing else, we must improve harm prevention".
Julie Tam said her son, Joshua, was one of many who make poor decisions at a vulnerable time in their lives.
"Obviously we wish young people would not take risks with drugs ... but in a civil society there must be measures we can put in place to try to save them from themselves," Ms Tam said at the NSW Coroners Court in Lidcombe on Monday.
"Six kids can't die at music festivals without some part of the rules changing."
She hopes an inquest into the preventable death of her son and five others will address the issue of "so-called recreational drug use" and stop other families from experiencing the pain of their "new normal" without Joshua.
His death is one of six at NSW music festivals between December 2017 and January 2019 being examined by Deputy State Coroner Harriet Grahame.
Alexandra Ross-King, Diana Nguyen, Joseph Pham, Callum Brosnan and Nathan Tran, who also died after ingesting illicit drugs in hot weather, were aged between 18 and 23.
Counsel assisting the coroner, Peggy Dwyer, said autopsies indicated they died from MDMA toxicity or complications from MDMA use.
They also exhibited soaring body temperatures - some above 41C - respiratory problems, muscle spasms, cardiac arrests and in some cases out-of-character aggression.
Dr Dwyer said Mr Brosnan took six to nine capsules before collapsing at Sydney's Olympic Park train station after attending the Knockout Games of Destiny.
Ms Ross-King consumed two half-pills on her journey from the Central Coast in a mini bus to Parramatta Park earlier this year and two more pills upon her arrival at FOMO festival.
"She told her friends that because she was nervous about being caught by the police, she took the drugs at once like that," Dr Dwyer said.
The inquest will attempt to identify the common themes as to the cause of deaths and lessons as to how they might have been prevented.
In each of the six instances the coroner will consider whether medical treatment and subsequent transfer was adequate and appropriate, and if effective harm minimisation strategies were in place at the festivals.
NSW's chief health officer Dr Kerry Chant is expected to give evidence that there has been a recent, substantial increase in drug-related harms associated with a small number of the state's music festivals.
The chief executive of the NSW Users and Aids Association has also prepared a statement noting anecdotal evidence suggests up to 95 per cent of young festival patrons use illicit substances.
Further experts will be called to testify about shade tents and cool down areas, access to water, information and peer support, law enforcement and drug checking - also known as pill testing.
"In this courtroom there is no judgment of the young people themselves," Dr Dwyer said.
"These six young people were beautiful souls who have been lost to us. Without exception, they were talented, social and community-minded."
Their deaths came as an incredible shock to their parents who were not aware of their child's interest in drugs, she said.
Ms Grahame offered her condolences to the families of the deceased.
"They could be any young people who go to music festivals and partake in drugs as many young people do," she said.
"These are our young people ... and we owe them a proper investigation of the circumstances in which they died."
The inquest will run for two weeks with further hearings in September.