Henrik Eide Dahl collapsed in the cafeteria of his school at the end of a so-called 'LAN party', a group gaming orgy played on computers linked together on the school's Local Area Network.
"I was playing Call of Duty. Then everything went dark and I passed out," Dahl told Norway's NRK network.
The teen was flown to hospital in Lillehammer, where his condition worsened, with his kidneys starting to fail. After he fell into a coma, he was kept alive by a respirator and a drip.
"When I woke up, I was terrified," Dahl told NRK
. "The first thing I remember from the hospital is that my brothers were sitting at the edge of the bed and crying."
He spent a total of 13 days in hospital, and is still taking medication to control his high blood pressure.
"It has been very scary, and I have learned that it is not good to drink that much energy drink," he said. "But it's getting better and better every day. I'm starting to feel normal now."
Anne Kathrine Duns, a doctor who treated him in Lillehammer, said that Dahl had been close to death.
"It was severely life-threatening. The central nervous system, cardiovascular system, lungs and kidneys were affected."
She said that despite several tests, she and her fellow doctors remained uncertain as to what exactly had caused Dahl's collapse, although she said she suspected the energy drink played a role.
"We find no underlying disease in Henry, so for now we are attributing this to the consumption of large amounts of energy drink," she said.
Helle Margrete Meltzer at the Norwegian Institute of Public Health said that Dahl's body could have reacted to something in one of the cocktail of different energy drinks he had consumed.
"I've never heard of such a powerful reaction to caffeine here in Norway," she said. "But there are more substances in energy drinks than caffeine, including some amino acids and artificial sweeteners, so it may be a combination of several things in the drink that has triggered the reaction."
While Dahl is still on medication, he is expected to eventually make a full recovery.
Correction: An earlier version of this article stated that Henrik Eide Dahl drank eight litres of an energy drink. In fact, he is believed to have drunk eight half-litre portions, totalling four litres.