Ruby Rose. Picture: Instagram

Ruby Rose is devastated that her friend Demi Lovato took a suspected overdose earlier this week but she's convinced she'll bounce back "even stronger."

The 25-year-old singer - who has battled with drug and alcohol addiction in the past - was taken to Cedars-Sinai Medical Center in Los Angeles on Tuesday following the alleged incident, but her friend is hopeful she can "defeat" her demons. 

Taking to her Twitter account after the news broke, Ruby said: "My whole heart and my whole soul is with @ddlovato today. I adore you and so does the entire world. You will fight this and you will come out of it even stronger. Addiction is powerful beyond measure, but you can defeat it. I love you. (sic)."

However, a fan slammed her use of words during her touching message and claimed there's no way anyone with addiction can "beat it" as it'a a "lifelong condition."

To which the 'Orange is the New Black' star hit back: "I have a lot of experience in this area and I disagree. You beat it... one day at a time. 

"And it IS CHALLENGING and it takes a support network. (sic)"

The 32-year-old actress has grown close to Demi in recent months and the pair even sparked speculation there were dating after flirting up a storm on social media. 

Meanwhile, law enforcement sources initially told TMZ that Demi had apparently overdosed on heroin, but it now appears that is not the case. 

The 'Cool For the Summer' hitmaker is said to have refused to tell paramedics what caused her to overdose, and no drugs were seized at her home. 

She was reportedly brought back to consciousness with Narcan, which is used to block the effects of opioids, and is now recuperating in hospital with her loved ones. 

Demi had been clean for six years but candidly confessed to a lapse in her sobriety in her recently-released track 'Sober'.

Lyrics to the song featured her apologising to her friends, family and fans for hitting the bottle.