A coroner has highlighted New Zealand's drinking culture, ruling the role "senseless" peer pressure played in the case of a teenager who drank himself to death.

Mitchell David Heward, 17, died on February 12 2016, as the tragic consequence of excessive alcohol consumption.

The inquest findings into the teen's death, released today, found that Heward was pressured to drink when he went to Lake Kaniere, on the West Coast of New Zealand's South Island, with a group of friends.

The group, aged between 14 and 18-years-old, took a significant amount of alcohol with them, and Heward is believed to have drank beer, vodka and Midori until he lost consciousness.

He could not be revived and died at the lake, coroner Anna Tutton said.

The alcohol was supplied by two members of the group who were aged 18 and 21.

Heward was found to have 349mg/100ml of alcohol in his system, which is almost seven times over the legal blood alcohol limit for a New Zealand driver over 20 years old.

"Mitchell's death was the tragic consequence of excessive alcohol consumption by a young person, in a group in which pressure to drink was applied. His death was senseless, and a sad illustration of the prevalent drinking culture," the coroner said.

"It is critical that young drinkers, particularly, appreciate the seriousness of the dangers of binge drinking, and to know what to do if someone becomes unresponsive after drinking."

A pathologist who conducted the autopsy commented that this was enough alcohol to cause severe intoxication, which could lead to death, Sutton said.

The doctor concluded that the cause of death was aspiration of vomitus (choking on his vomit) due to "profound, severe alcohol intoxication".

Jan Heward said her son wasn't a drinker and alcohol had never been an issue in their family.

"He was a good kid. He had focus and was saving really really hard. He had bought himself a car and had a motorbike, had furnished his home and he and his friend were planning to buy a farm together and go overseas.

"He was going places... I don't know if you ever get over it.

"It needs to be drummed into teens that alcohol can kill you. Don't believe stupid things; peer pressure from other people saying it's going to be alright. Mitchell was a solid kid.

"Nothing is going to bring him back."

Perrin, in a speech at his school after his best friend died, talked at length about the pain he had caused, and the perils of underage and excessive drinking.

"I tried to resuscitate Mitchell once I saw what had happened and how ill he really was.

"The one thing that keeps me awake at night is that I failed to resuscitate Mitchell.

"I was unable to help him, I was unable to do anything for him. I really tried my best, and it wasn't enough."

The risk of underage drinking or abusing alcohol was too high, Perrin said.

The law was there for "a damn good reason, and it's to protect us from ourselves".

There was a drinking culture in New Zealand - especially among young people.

"We drink to get drunk, rather than drink socially. We drink until we fall."