"The thought of it makes my nose bleed," he said years later.
In 1989, however, O'Toole had a big stage success with "Jeffrey Bernard is Unwell," a comedy about his old drinking buddy, the legendary layabout and ladies' man who wrote The Spectator magazine's weekly "Low Life" column when he was sober enough to do so.
A month before his 80th birthday in 2012, O'Toole announced his retirement from a career that he said had fulfilled him emotionally and financially, bringing "me together with fine people, good companions with whom I've shared the inevitable lot of all actors: flops and hits."
"However, it's my belief that one should decide for oneself when it is time to end one's stay," he said. "So I bid the profession a dry-eyed and profoundly grateful farewell."
O'Toole's marriage to Welsh actress Sian Phillips ended in divorce in 1979, after 19 years of marriage. The couple had two daughters, Kate and Pat.
A brief relationship with American model Karen Somerville led to the birth of his son Lorcan in 1983.
His daughter Kate said the family had been overwhelmed by expressions of sympathy.
"In due course there will be a memorial filled with song and good cheer, as he would have wished," she said in a statement.
Associated Press Writers Gregory Katz, Raphael Satter and Danica Kirka contributed to this report.
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