Speaking at a press conference last week, the former glamour model shocked journalists into silence with her revelation, claims Now magazine.
When asked to declare the rudest thing she had ever done, Price is quoted as replying: "I f**ked Alex up the arse with a vodka bottle."
The 34-year-old reality TV star was promoting her upcoming romantic novel In The Name Of Love.
Since separating from Reid in January 2011, Price has launched a number of scathing attacks on her ex, branding him a "tranny" in an interview published last month.
Katie Price has been engaged to Argentinian model Leandro Penna since April.
Cagefighter Reid is also engaged to Big Brother star Chantelle Houghton. The couple welcomed a baby girl ten days ago.
> Katie Price's ex lovers and reality TV: A history - video
Photo gallery - Katie Price rides into her book launch last week: