Photo: Lindsay Visits Emergency Room

Could Lindsay Lohan, who until recent weeks had been living a relatively restrained life since exiting rehab last fall, be getting back to her old ways?

Late Thursday night, photographers snapped shots of the young star and her rumored girlfriend, DJ Samantha Ronson, as they exited Century City Hospital in Los Angeles, where sources tell OK! the couple had spent more than two hours in the Emergency Room area.

"Lindsay was visably stressed," one eyewitness tells OK!.

<a><img src="https://farm3.static.flickr.com/2185/2535793451_631ef400d9_o.jpg" width="400" height="600" alt="Lindsay Lohan, Samantha Ronson" /></a>

(photo: Finalpixx.com)

The reason for the visit to the hospital is currently unknown. Stay tuned as details develop.

Calls for comment to Lindsay's rep have not yet been returned.