The rocker has been open about his past struggles with depression and anxiety, and he has now revealed that in the 1990s, he was also suffering from panic attacks and a form of schizophrenia.
The condition causes symptoms such as hallucinations and delusions, and Davis, 44, admits it was a scary time in his life because he became convinced the people around him were trying to poison his food.
In a video made for the You Rock Foundation, a charity which helps sufferers of depression, Davis says, "It was the most horrible thing when I got my first panic attack. I thought I was going to die. I didn't know what was going on... It was when I was drinking...
"It's so hard to deal with anxiety and depression because you don't know what's going on; you feel like you're going crazy. And eventually because I started getting really paranoid and thinking that medicine was bad for me... I wouldn't take any kinds of meds or anything like that... I actually turned a little bit schizophrenic for a while. Anxiety can do that to you... I was feeling like my food was going to be (poisoned)... People were trying to poison me... It was a really, really tough time..."