The HSE said Connolly Hospital estimates 36 people presented at its emergency department from the event, though not all would have been brought by ambulance and not all would have been injured within the concert arena.
Seven separate stabbings took place during the show headlined by Swedish House Mafia, the second of three major events staged in the park in the past week.
Gardaí had arrested a 23-year-old man, who was yesterday detained at Blanchardstown Garda Station, in connection with the violence. He was charged last night and will appear in the criminal court complex in Dublin at 10.30am.
However, gardaí believe there were a number of culprits for the stabbings.
Some victims were stabbed in the abdomen, while in other cases people were slashed in the legs and back. Three victims were being treated yesterday in James Connolly Memorial Hospital in Blanchardstown, two of whom were seriously injured. Others treated at the same hospital were released. All those who sustained stab wounds were male and aged in their late teens or 20s. The two men who sustained the most serious injuries were both in their 20s.
It also emerged yesterday that a man in his 20s collapsed at the concert and later died at Connolly Hospital from a suspected overdose.
It is understood the man went to the paramedic tent and complained of being ill when he collapsed.
Organisers MCD said it was “extremely shocked and saddened” by the man’s death and it would help the gardaí with its inquiries.
It emerged two other people died of drug overdoses in Connolly Hospital on Saturday night and Sunday morning, though at least one of those had not attended the concert.
Gardaí yesterday were trying to identify the person who collapsed at the Phoenix Park event.
A member of the Dublin Ambulance Service yesterday said at one stage there were five Dublin ambulances in the Phoenix Park on Saturday dealing with cases.
“We started to get inundated with calls from about 3.30pm,” he said. “People were found unconscious through either drink or drugs at the Castleknock gate, Ashtown Gate and the Papal Cross.”
A Dublin Fire Brigade member said: “We had calls coming in fast and furious. I think the emergency cover for it [the concert] was badly organised. I am sure there will be an investigation into it from our side.”
MCD said: “Five ambulances including three emergency ambulances and two Order of Malta ambulances were on site as approved by the HSE Emergency Management Office and in accordance with event licence conditions. At no stage was it required to call on any external ambulances resources.
“Ticket holders entering the site were subject to a search permissible by law... All CCTV footage captured from the area has been supplied to the gardaí.”