Eight people were taken to hospital, including one in a critical condition, from the Electric Avenue music festival.
St John spokesperson Siobhan Campbell said 242 people were on-site at the festival in Christchurch’s Hagley Park yesterday.
A further eight needed hospital care – with one person critically unwell and the rest in a mild to moderate condition, Campbell said.
Electric Avenue is Christchurch’s biggest outdoor music festival.
Campbell said the Privacy Act prevents St John from saying whether the patients’ conditions were drug related.
But said a team of medics were on site to treat people needing medical attention for anything from dehydration to drug use.