Wilmer Valderrama has visited Demi Lovato in hospital.

The 38-year-old actor stopped by Los Angeles' Cedars-Sinai hospital on Wednesday (25.07.18), following his former girlfriend's apparent overdose on Tuesday (24.07.18), sources told People magazine.

It was previously claimed Wilmer - who split from Demi, 25, after six years of dating in June 2016 - had been left very ''shocked'' by the 'Skyscraper' singer's hospitalisation.

A source previously said: ''He knew she was going through a tough time but he wasn't prepared for this.

''He saw her through so many ups and downs and was her rock through some of her darkest moments. To see her back in such a sad and vulnerable place is heartbreaking for him.

''He always cared deeply for her and they truly remained friends after they broke up.

''Demi always hoped they would end up back together in the future. He's the love of her life and vice versa.''

Meanwhile, it has been reported that Demi - who publicly revealed she'd relapsed in her addiction battle with her new single 'Sober' last month - fired her sober coach, Mike Bayer, just three weeks before her suspected overdose on a mystery substance.

A source said: ''She and Mike started having arguments back in March.

''He felt like she was always making excuses for herself, her bad behaviour and not telling him the truth about what she was up to. He called her out on her s**t. which she did not appreciate.

''She fired him a few weeks ago - they had a big argument and then they unfollowed each other on social media. It has been very ugly and messy as this guy was like 'her rock' that she leaned on after she and Wilmer broke up.

''She has been alienating people all around her, but she is very much well liked in Hollywood - people just want her to get well and get help.''

It's believed the 'Sorry Not Sorry' hitmaker - who has been battling with alcohol and drug abuse for years - hired Mike after she first sought help in rehab for her addictions back in 2010.