The man choked on his vomit and with no one around to save him, he came close to death, Mr Thompson said.
Another student, who had a heart problem his friends did not know about, came close to death after taking part in a flat initiation.
"He was told to attend an initiation at his would-be flat, where the current flatties would make him do 'necessary' tasks before he could be allowed to rent the flat. He was given a bong to smoke, a bottle of red wine and a large amount of beer. He lost consciousness, fell to the floor and began to froth at the mouth," Mr Thompson said.
The student had a "long stay" in hospital and missed lectures for a month.
OUSA president Francisco Hernandez said a big part of the campaign was about empowering students to "say no" if they did not want to take part in drinking games or continue drinking.
"It's about respecting your mates and yourself. Not everyone feels they can say no to some of the extreme stuff that goes on," Mr Hernandez said.
It was also about encouraging students to learn their limits.
"As always we're down for a good time. Just don't take it too far. You don't want to end up hurting yourself or someone else or risking your place at university."