Before Demi Moore
, the actress "was having what seemed like seizures" at home, a source tells PEOPLE.
"Concerned friends called 911," the source says.
The actress, 49, is being treated for what her rep says is "exhaustion," as friends privately express concerns
about her declining health and mounting stress.
While the cause of the reported seizure wasn't immediately known, a second source insists to PEOPLE that Moore "did not attempt suicide."
TMZ, meanwhile, reports
that Moore went to the hospital after a bad reaction to nitrous oxide.
Moore's reps have not commented since releasing the initial statement.
The former Ghost
star, who has had a rocky couple of months that included a split from
husband Ashton Kutcher
and a death of a close friend, dropped out of her recently casted
role as Gloria Steinem in the upcoming Lovelace
Additional Reporting by LIZ McNEIL