"The Essendon football club came forward to ask for the investigation, they are fully aware of the timelines and we are not expecting anything to eventuate for two to three months," Demetriou said.
"The club is going about it the right way, the chairman is leading the way, they are performing on the field.
"If it takes two months, it takes two months.
"We've already put our measures in place to enhance our policy and enhance the integrity of the code with some sweeping changes.
"I'm currently visiting every club, players included, to make sure they understand the importance of this issue."
Demetriou mentioned a number of factors that were contributing to the time the investigation was taking.
"There are a number of players and officials to be interviewed and probably reinterviewed, that takes time," Demetriou said.
"There's also issues around particular substances that have to be analysed, that takes time.
"We could be talking about July, August before any findings and if that's the case, that's the case.
"The Essendon football club is conducting its own internal investigation about the governance and the processes," he said.
-AAP