James Haberfield assaulted a female paramedic after consuming "a cornucopia" of drugs at Victoria's Rainbow Serpent festival in January.

The 22-year-old became the first person under new Victorian laws to be slapped with a compulsory treatment order for attacking emergency workers.

But in a move infuriating emergency workers, Haberfield on Wednesday avoided a minimum six-month jail term also required under the new laws, which came into effect last October.

Paramedic Monica Woods, who cried in the court as the sentence was delivered, has not returned to work since the attack and suffers from post-traumatic stress disorder and anxiety.

Victorian Ambulance Union secretary Danny Hill said emergency workers had received the message the courts didn't have their backs.

"Will it take the death of a paramedic before the government takes action?" he said after the sentencing.

Premier Daniel Andrews said the Director of Public Prosecutions should urgently consider appealing the sentence.

"Our thoughts are with the victims of this completely unacceptable attack," he said in a statement.

Melbourne Magistrates Court was told Haberfield went missing in an "acutely psychotic state" after the four-day alternative music and arts festival, during which he'd consumed "a cocktail of drugs" including ice, MDMA and ketamine.

The university student knocked on the door of a Coburg home, walking inside and terrifying the residents, who were unknown to him.

When the ambulance arrived to collect him, Haberfield punched Ms Woods in the face and put her in a headlock, squeezed and pinned her to the rear corner of the ambulance.

Fellow paramedic Sam Smith avoided Haberfield's punches, pressed the vehicle's duress button and sedated the youth.

Haberfield stayed in hospital for more than a week receiving treatment.

Ms Woods suffered whiplash to her head and neck, a hematoma and swelling to her cheek, as well as her psychological trauma.

Magistrate Simon Zebrowski said Haberfield's impaired mental state that day wasn't solely due to self-inflicted intoxication as he had pre-existing autism spectrum disorder and a major depressive disorder.

He said Haberfield, in a psychotic state, had a delusional belief his safety was at risk after the "cornucopia of illicit drugs" he'd ingested.

A psychiatric expert said he would be at an "acute risk" of suicide in jail.

Mr Zebrowski said sending the "mortified, dismayed and deeply ashamed" young man to jail "would have a disproportionate and catastrophic effect" on his future.

"The message needs to be sent to the community that emergency workers are not punching bags," he said, before giving Haberfield an 18-month community corrections order including mental health and drug treatment.

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Australian Associated Press