The RSPCA has no leads on the whereabouts of three joey koalas stolen from a wildlife carer's enclosure south-east of Brisbane.

The three orphaned joeys were taken early yesterday morning and require specialised care and medication.

RSPCA vet nurse and wildlife carer Sam Longman said they were among 10 koalas she was nursing back to health at her bayside home at Ormiston, south of Brisbane.

She said none of the three joeys would survive on their own.

"They can climb but don't have the smarts they need," she said.

"They go through a process with us carers stage by stage to get them ready to go back to the wild and they're not anywhere near that stage to be released, they're still very dependent on me.

"They're going to be becoming dehydrated by now, they've missed two medications so I'm extremely worried.

"I don't understand why they would take them or what the benefit of taking them would be to somebody."

'Anybody could jump the fence'

Ms Longman said she went to work on Thursday night and noticed her gate open and the joeys missing when she arrived home on Friday morning.

She said she kept the koalas in an enclosure near her front door.

"You have to walk through the side gate to get access to the enclosure, so anybody could jump the fence, we've only got low fences, or somebody's walked through the side gate."

She said she searched trees around the neighbourhood but then realised the open gate and the movement of several items in her yard meant someone had taken them.

"There's no way for them to be able to get out of my enclosure. I've had a lot of joeys through that enclosure and never had any escape.

"[They are] still very reliant on me, two of them are still quite ill and are on daily medication."

She urged whoever was responsible to drop the joeys back to her, saying there was a cage at her letterbox.