Charlie Sheen's ex-wife Brooke Mueller admitted to her friends that she was abusing prescription drugs before she was hospitalized for exhaustion last week, according to TMZ.

Mueller has been telling her friends that she abused Adderall, for which she has a valid prescription, to treat her attention deficit hyperactivity disorder, according to the report.

According to friends, she admits she "fell off the wagon," and took more than she was supposed to.

Brooke was hospitalized in Los Angeles on Friday for exhaustion and dehydration. Her assitant found her unresponsive while she was naping, according to reports.

She was discharged the same day one hour later and was diagnosed with exhaustion and dehydration.

Her representative denied rumors spread by TMZ that she overdosed.

Mueller was arrested in Aspen, Colo. in 2011 after allegedly assaulting a woman at a bar, the Los Angeles Times previously reported. At the time police found her with four grams of cocaine.

She publicly went to rehab early this year , according to US Weekly.

Mueller and Sheen married in 2008 and had twins Bob and Max.

Mueller has been dating country musician Jaron Lowestien for several months.

"Jaron is from Nashville, and Brooke and the boys have been spending a lot of time with him in Tennessee," a RadarOnline source said. "Brooke and Jaron are basically living together and he is a great influence on Brooke who has had issues over the years with substance abuse. Jaron isn't a party animal, in fact he is the opposite of Charlie Sheen as he doesn't drink or even smoke."