demi-synthetic-pot.jpgYesterday Demi Moore's 911 call hit the internet, and friends of the 49-year-old actress told dispatchers that she had collapsed after smoking a mysterious substance.

An unidentified female caller revealed that it was "not marijuana," adding that it was "similar to incense." Demi had difficulty speaking, convulsions and a fever, and now doctors are speculating that she may have smoked synthetic cannabis, also known as "K2," "Spice" or "herbal incense."

Dr. John Sharp, MD, a faculty member of Harvard Medical School explained to Us Weekly that the drug is similar to marijuana but "not necessarily safer" and it doesn't show up in most drug screenings. Some medical studies have linked the use of synthetic cannabis to psychosis, heart attacks and convulsions, so Demi's reaction does seem consistent with someone using the drug.

And that (along with nitrous oxide) weren't the only substances Demi was allegedly using. Prior to her trip to the ER, Demi had been drinking excessive amounts of Red Bull energy drinks, and a source told Us that she drank 12 cans in one evening!