South Sydney chief executive John Lee has confirmed Rabbitohs pair Dylan Walker and Aaron Gray took too much prescription medicine that led to their hospitalisation on Tuesday morning.
Both players were brought to St Vincents hospital in a critical state but are now in a stable condition.
The Rabbitohs duo were on painkilling medication after undergoing post-season surgery last week.
Lee was careful not to say that the players had overdosed on painkillers.
"What we're saying is they were prescribed a level of medication, and this is medication that's not taken for fun," he said.
"This is medication that is taken for pain, and it is becoming clear that they took too much of that medication.
"I'm not going to use emotional words. I'm not a medical professional, to give you the right medical term.
"We'll need to know what the toxicity information is at it becomes available."
The police have already begun investigations on the incident, while the NRL have also indicated that their integrity unit would look into the matter.
- AAP