Speaking at a public talk as part of the Galway Film Fleadh, the Oscar-winning actress said she was unlikely to return to the stage or screen.
"I'm semi-retired now. I've been 40 years in the business, so no," said the Dubliner.
She added, however, that she might make an exception for certain directors including Virginia Gilbert, with whom she made A Long Way from Home, or Tom Fitzgerald, who directed her in Cloudburst.
Fricker said she had been in ill health and only recently left hospital. She said it had given her a first-hand look at the pressures faced by nurses.
She also apologised to the audience for eating sweets, saying it was necessary to avoid dry mouth as a result of medication.
She also told how she almost missed out on a role in My Left Foot, and that it was only through the efforts of her then husband, TV producer Barry Davies, that she was able to take on the role that changed her career.
"I was busy doing Casualty at the time and I wasn't pushed about doing film at all," she said. "But my husband moved mountains and got the dates changed."
Speaking of her five years on Casualty, Fricker said British Prime Minister Margaret Thatcher had wanted the show scrapped after the first season because of its description of hospital overcrowding.
The actress also praised Davies, who died in 1990.
"He became an alcoholic, but before that happened he was one of the best directors I ever came across and one of the nicest people I ever came across. I learned an awful lot from him," she said.