"There are first-hand reports that many attended the party having been drinking beforehand and that the application of paint in an area with a slippery floor led to a number of falls and head injuries," Dr Poore's letter said.
It was co-signed by fellow medical officer of health Dr Keith Reid.
"There is another side to the setting of the world record at the Illuminate Paint Party. Once again, the combination of alcohol and large numbers of young people has resulted in significant risks to individuals and our taxpayer-subsidised emergency services were placed under considerable strain," the letter said.
"Dangerous drinking is a serious issue in our community and moderation is urgently needed," it stated.
About 5000 people attended the party at Forsyth Barr Stadium.
Dunedin police had a presence at the event, as customary for all large gatherings, Senior Sergeant Kelvin Lloyd said.
No-one was arrested at the party and police, overall, were happy with the behaviour of those attending.
Most revellers made their way from the venue to their homes without any problems, Snr Sgt Lloyd said.
"We were pretty happy with the follow-on from the event. We know there were varying degrees of intoxication, but it certainly didn't cause us a great deal of angst after it had finished."
Two couch fires were lit by groups of people in the student quarter after the party, although it could not be confirmed whether the incidents were related, he said.
"There were some large gatherings after the party, but generally it was pretty good."
At the stadium, clean-up crews had a daunting task removing four tonnes of UV paint.
Clean-up overseer Karen McCreath said cleaners worked through the night to return the stadium to its pre-paint condition.
The clean-up began at 11pm on Wednesday and was still going at noon yesterday.
After 15 hours, Forsyth Barr Stadium chief executive Darren Burden was happy with the state of the venue.
"The event went remarkably smoothly and the clean-up crew did an outstanding job," he said.
Event organiser Jamie Templeton was impressed with the venue and the 300-odd staff involved in the party.
He deemed the world record-breaking event a success.
