The actor, who plays family matriarch Agnes Brown, is working on turning his creation into a stage musical that will tour Ireland, the UK, Australia and New Zealand.
O'Carroll is enlisting the help of some top Irish talent to create some memorable tunes for the production.
"I'm writing a new show for 2019, Mrs Brown: The Musical. It will still tour, I wouldn't stay in one place," he said.
"One of the reasons why I haven't done Broadway or London is because they want you to stay in one place for six months. "That's like a real f**king job.
"Everyone will be singing. It's hard writing anything. I've written a few songs. It won't be just me.
"The Script, I'm hoping, will do a number. Picture This will do one.
"I haven't written the story yet, but that's where we are heading."
O'Carroll insisted that all of the show's cast members are talented singers and added that some of them will also be learning to rap for the musical.
"We are very lucky because everybody sings. Some of them have amazing voices, and then there will be a couple of them who will rap. It will be fun," he added.
"It's going to be Mrs Brown: The Musical, but I'm never going to veer away from the comedy," he told the Herald.
This year's Mrs Brown's Boys Christmas special will see viewers introduced to the actor who is replacing Rory Cowan.
The character's new look will be as a result of extensive plastic surgery and O'Carroll is confident viewers will take well to the new actor.
"The guy who is replacing him is very good. He's Irish," he said.
"We looked at a few people. It was our producer Fiona Gibney who said, 'What about this guy?'
"I didn't want to do a replica Rory.
"It has to be completely different because the whole idea of this plot is that Rory has had plastic surgery. This would definitely be a big break for him."
O'Carroll was speaking at the 13th annual Celebrity Ward Walk at Our Lady's Children's Hospital, Crumlin.
Stars including O'Carroll's son Danny, Mary Byrne, Rosanna Davison and Ronan Keating took part in the event, meeting children in the wards.
"Today is a lesson in the resilience of children. You walk in the door and the first thing they say is 'Happy Christmas'. It's heart-warming," said O'Carroll.
"I have done it every single year and never left this hospital on this day without counting my blessings."