Mueller Headed South of Border For Extreme Rehab

7/17/2011 9:30 AM PDT

Charlie Sheen's Ex Brooke Mueller Goes South of Border For Extreme Rehab

Brooke Mueller is going to Mexico to ingest a bunch of hallucionogens -- but not for fun -- to break her addictions.

Sources connected to Brooke tell TMZ ... Brooke is going to a treatment facility in Cancun that specializes in prescribing a drug that is not legal in the U.S. It's called Ibogaine, a substance extracted from an iboga plant. Some studies show it interrupts addictions to alcohol, cocaine, methadone and heroin. 

Brooke is saying the program is seven days and it's "extreme," but she's confident it will "rewire" her brain to break her addictions. 

Brooke has been hospitalized since her confrontation Thursday on a United jet bound for Cancun. We're told she'll make the trip when she's released from the hospital.