Rose McGowan has given her support to the campaign to "free" Britney Spears from her conservatorship in an emotional Instagram post referencing the late actress Brittany Murphy.

The actress and activist, who has been a vocal advocate for the #MeToo movement and ending patriarchal power in Hollywood, took to Instagram to remember the Clueless star, who died aged 32 in 2009 after suffering from pneumonia brought on by anaemia and prescription drug use.

"Brittany Murphy was a lovely, amazing, force of nature. Hollywood did not treat her with the respect she deserved, making her feel less than for not being a 'typical' beauty," Rose wrote. "And I saw what it did to her- it ate her up. Hollywood kills, sometimes slowly, sometimes quickly, but it kills. Your soul, your mind, your self-esteem, pressure of perfection... it's endless and twists your mind."

Rose went on to link Brittany's fate to her near-namesake, the Toxic singer, who has been under the conservatorship of her father Jamie and carers since he took on responsibility for Britney's welfare and finances following her public breakdown in 2008.

"I'm so sorry you didn't make it, Brittany. Your talent deserved better, your soul deserved better," the Scream star added. "There's another Britney on my mind today, too, one that is alive, one that can be saved from the leaches that are controlling and trafficking her. Free all the Britneys and all those who get hurt by the trauma of Hollywood values and toxic 'rules.' #FreeBritney #BrittanyMurphy."

When Britney entered rehab last year, rumours emerged that she was actually being kept at the facility against her will by Jamie - who has now handed over his duties to the star's longtime care manager, Jodi Montgomery, until at least 22 August.

Despite fans' concern and her troubles, the Stronger hitmaker recently took to Instagram to insist she's fine and feeling "happy".