Demi Moore's Hospitalization Due To Prescription Drugs, Partying Hard & Most Of All: Nitrous Oxide Or Whip-Its!!!

As we all send healing thoughts Demi Moore's way, questions remain over what led to her reported hospitalization for "exhaustion." From a rumored seizure to her apparent partying...

On Monday night, the worryingly slimmed-down star, 49, began "shaking" and "acting like she was suffering from a seizure," reports E! News. A female friend who was visiting Demi's home called 911, and paramedics eventually transported her to a local hospital.

Radar Online also diagnoses a seizure, with a source suggesting, "She has not taken care of her health at all lately and has lost a ton of weight."

E! adds that the actress's inner circle has been concerned about her increasingly attenuated appearance, which seemed to get worse after she pulled the plug on her six-year marriage to Ashton Kutcher in November.

According to TMZ, which first reported Demi's hospitalization, she's receiving treatment for "substance abuse" issues, and claims one of the substances involved is nitrous oxide, known to the college crowd as "whip-its."

A friend says she "lapsed into semi-consciousness" after allegedly inhaling a "dangerous amount" of nitrous.

But were other substances involved too?

According to People, Demi's confidants have been "desperately concerned" for her because she's seemed "stressed out, tired and clearly [has] not taking proper care of herself."

"Really, it was over the last year her friends saw a change," states a source. "She wasn't sleeping as well, didn't seem to be eating and looked really gaunt."

The mag points the finger at prescription drugs, and says they also played a role in her split from Kutcher, 33.

"It was a sticking point for Ashton," another insider tells People. "He wanted her to take care of herself and get a hold of things, and she wouldn't. Her family and friends have been really worried."

Another spy offers this unvarnished assessment: "Demi is a mess."
"[Ashton and Demi] both like to party, but she tends to wear it all over her," explains a mole. "She can talk too much, get verbally abusive and weigh on your nerves."

And Moore's behavior in the weeks leading up to the 911 call may have hinted at her issues ...

People reports that on Jan. 11, Demi hit hot spot Beacher's Madhouse in Los Angeles with daughter Rumer Willis, 23.

Dressed in a miniskirt and quaffing Red Bull, Moore initially "kept to herself," relays an eyewitness. "But she started loosening up and getting into party mode. She seemed really happy to be out with her daughter's friends."

Moore also seemed really happy in the company of dark-haired TV actor Ryan Rottman, 27, who has appeared on "90210."

"She found ways to touch him all night, and at one point when he was in front of her, she was grinding on his butt," says the spy, who also recalls that Rottman's "shirt came unbuttoned, and she started tickling his bare chest playfully."

Us, meanwhile, has a slightly different take, quoting an onlooker as saying the "super skinny" star was "table dancing while three guys sat there watching. She was trashed."

This wasn't the first time in recent days that Demi got her dance on for an audience ...
On Christmas Eve, Moore "danced up a storm" at a poolside bar in the Turks and Caicos while Rumer played DJ.

"Demi was dancing seductively for all the guys [at the bar] and they were going nuts," relayed an eyewitness.

On Tuesday afternoon, TMZ snapped Rumer smoking a cigarette outside the hospital where her mother is reportedly being treated. Looking "visibly distraught and concerned," she paced and talked on her phone.

So, where's Ashton been amid Demi's health drama?
Kutcher has spent the last few days in Brazil, where he sat front row at a fashion show, posed for a catalog shoot, took pictures with some female fans and tweeted a photo showing him giddily "surfing the streets of Sao Paulo."

On Tuesday, E! News and People spotted the dewy blonde-seducing "Two and a Half Men" star partying with pals into the wee hours.

His agenda this week has also included taking in a Bruno Mars concert and hanging with pregnant model Alessandra Ambrosio and her fellow cat-walker Ana Beatriz Barros.

"He doesn't stop!" crowed one Brazil-based outlet.

In other words, Ashton doesn't appear to be making a beeline back to his estranged wife's side.

Moore and Kutcher last crossed paths on Jan. 13, when they attended the same pre-Golden Globes bash in Los Angeles.

The exes gave each other a wide berth, although Rumer spent a few minutes chitchatting with her stepdad before returning to her mom's side, reports People.

"I saw him briefly say hi to her, but that was it," a bystander adds to Us Weekly. "They spent most of the evening keeping a distance."

"Because of the stresses in her life right now, Demi has chosen to seek professional assistance to treat her exhaustion and improve her overall health," her rep said in a statement. "She looks forward to getting well and is grateful for the support of her family and friends."

Moore, who briefly checked into rehab in 1984, recently opened up to Harper's Bazaar about her "love-hate relationship" with her body.

"I think I sit today in a place of greater acceptance of my body," she explained, "and that includes not just my weight but all of the things that come with your changing body as you age to now experiencing my body as extremely thin -- thin in a way that I never imagined somebody would be saying to me, 'You're too thin, and you don't look good.'"

Demi admitted that when she's "at the greatest odds with my body, it's usually because I feel my body's betraying me, whether that's been in the past, struggling with my weight and feeling that I couldn't eat what I wanted to eat, or that I couldn't get my body to do what I wanted it to do."

Photos taken from FS2/WENN, Ivan Nikolov/WENN, Lester Cohen/ Wirelmage.com, Henry S. Dziekan/Wirelmage.com