The 21-year-old has previously been in rehabilitation centre for addiction issues, an eating disorder and self-harm.
"Some people can smoke and drink recreationally. I'm not one of those people. If I do that, it will spiral out of control very quickly. I've lost the privilege of being able to drink responsibly," OK! magazine quoted Lovato as saying, reports contactmusic.com.
Lovato also admitted that it was difficult to stay sober after her father passed away earlier this year.
"I've definitely struggled a lot with drug and alcohol addictions - even more than with my eating disorder. But I decided to stay strong when my father died. I worked so hard on my sobriety - I wasn't going to give it up," she said.
"When I feel like I want to give up I think to myself, 'No, what about the 17-year-old girl that's been free of self-harming for nine months?' If I give up my sobriety, that would mean it would be OK for her to go back to self-harming," Lovato added.
--IANS (Posted on 16-12-2013)