The 18 year old pulled out of the final dates of her South American tour with the Jonas Brothers last month (Oct10) and checked into a clinic to seek professional help for undisclosed personal problems.
Lovato was due to begin filming the third season of Sonny With A Chance in January (11), but TV executives have decided to resume production without her by re-writing the scripts and focusing the plot on other characters.
A Disney Channel spokeswoman tells Variety, "This allows her the time she needs to get well, without distraction or pressure. Again, we extend our ongoing support to Demi and her family as she works to overcome personal issues."
The move is said to be temporary and will allow Lovato to return once she is fully fit.