[Image via WENN.]
Sources close to Amy Winehouse tell PerezHilton.com exclusively that they believe drugs were not responsible for the singer's untimely death.
Instead, they believe Amy's passing was brought on by a massive seizure.
"The hardcore drugs completely wrecked Amy's nervous system," an insider tells us. "She gave up all that [hardcore drugs] a while ago but she was still drinking heavily, which would bring on seizures."
Amy had been suffering from seizures regularly and despite being warned by doctors kept drinking.
An official autopsy has yet to be completed.