The 16-year-old, who plays Raffy Morrison on the Channel Seven soap, took to Instagram to share the news with fans.
Alongside a picture of herself sleeping in hospital, Olivia wrote: "Hey guys, a couple of days ago I hit my head and was concussed with brain swelling."
The actress added, "I’m fairly crook at the moment and have been to hospital a couple of times but slowly improving. I won’t be on social media a lot due to the fact I’m sleeping like 12 hours a day but wanted to let you all know I’m still here and am trying to get better as soon as possible."
"Thanks for the constant support love you all lots x (also thanks mum for taking photos of me passed out)."
Fellow Home And Away stars took to the photo to send their well-wishes.
Penny McNamee wrote, "Sending lots of love and love healing vibes beautiful."
Georgie Parker echoed, "Please take your time getting back into everything. Love you sweetheart."
Olivia landed the role of Raffy Morrison on Home and Away in late 2016.
The young actress has showbiz in her blood, being the granddaughter of The Sullivans’ Reg Gorman, and her mother Kate Gorman played Sue Parker on Neighbours.
Wishing Olivia a speedy recovery!