Doherty was cast in the Aaron Spelling produced Beverly Hills, 90210 as bad girl Brenda Walsh and was regular until her departure during the fourth season. Aaron Spelling reached out of Doherty and cast her as older sister Prue Halliwell in his new supernatural series, Charmed, in 1997 along side Holly Marie Combs and Alyssa Milano.
Doherty played Prue for the series first three seasons until she decided to leave. Although it was claimed she was pursuing other opportunities, the increase of time devoted to Combs' character Piper and tensions between Doherty and co star Alyssa Milano.
Since leaving the show, Doherty has appeared in various reality shows.
Dougherty currently weighs in 620 pounds.