Lamar Odom was rushed to the hospital after being found unconscious and "foaming at the mouth" at a Nevada brothel on Tuesday. The former NBA and reality TV star has yet to regain consciousness, according to multiple reports, as friends and family gather at his bedside.

A source at the hospital told E! News the situation is being treated as an overdose. E! also reported that Odom may have suffered a stroke and "virtually every drug imaginable was found in his system." 

A Nevada sheriff said at a Wednesday evening news conference that a person who called 911 reported that Odom had been doing cocaine and had taken sexual performance enhancers.

Nye County Sheriff Sharon Wehrly said an employee for Love Ranch told 911 dispatchers that Odom was found unresponsive with blood coming from his nose and mouth.

The caller said Odom had been doing cocaine and had taken up to 10 tabs of a sexual performance enhancer over three days.

Odom's reality show with wife Khloe Kardashian aired on the E! network.

Officials at the Las Vegas hospital treating Odom, 35, would not provide any update or details regarding his condition.

TMZ reports Khloe and Kim Kardashian, as well as mother Kris Jenner, are by Odom’s side. On Wednesday morning, the Kardashians' half-sister Kendall Jenner tweeted a cryptic message.

Dennis Hof, who owns the Love Ranch and other legal brothels in Nevada, told FOX411 Odom had been staying at the Love Ranch for four days.

"He was polite and reserved, and he told multiple employees that he was there to get some privacy and spend some time relaxing," Hof stated.

Hof, however, told FOX411 that Odom seemed distraught on Sunday. 

"He got a call on Sunday and he was upset—he was visibly upset—but he got over it kind of quickly, and the moved on and kept having fun."

Two women went to check on Odom Tuesday afternoon after not hearing from for several hours and found him face down and unconscious.

When they turned him on his side at the direction of a 911 operator, Odom started "throwing up all kinds of stuff."

Hof told us Odom was “foaming at the mouth, laying on his right side. My management called 911. [The 911 operator] said ‘get him on his left side.’ He started throwing up profusely— some blood around his nose and mouth, and then the ambulance took him away.”

The brothel owner said his staff was told by paramedics at the time Odom “wasn’t going to make it.”  

Hof said Odom had been taking herbal Viagra and "did drink alcohol from our bar," including part of a bottle of cognac, since arriving, but had no knowledge of his use of any other drugs.

"My staff told Lamar ‘no drugs,’" Hof emphasized. 

He added that police searched the room Odom stayed in and looked through the star's belongings. 

The Nye County Sheriff's Department was called at about 3:15 p.m. PST Tuesday to Love Ranch in Crystal, Nevada, about 70 miles outside of Las Vegas for a report of an unresponsive man needing an ambulance, Sheriff Sharon A. Wehrly said in a statement.

Odom, who starred alongside his wife in an E! series titled “Khloe and Lamar,” was stabilized and taken to Desert View Hospital in nearby Pahrump, the statement said. Officials then tried to have him airlifted to Las Vegas, but the 6-foot-10-inch Odom was too tall for the helicopter that was available so he was driven by ambulance to Sunrise Hospital and Medical Center.

Odom, who won two NBA championships with the Lakers in 2009 and 2010, last played in the NBA in 2013, and saw recent reality TV fame through his marriage to Khloe Kardashian.

Kardashian filed for divorce in 2013, citing irreconcilable differences. The divorce has not yet received final approval from a judge. 

Recently aired episodes of “Keeping Up With the Kardashians” have touched on Khloe Kardashian’s tendency to keep in touch with her ex. The show has included several clips that show the youngest Kardashian sister calling Odom.

“Lamar and I loved each other deeply, and I don’t believe in acting like that relationship never happened,” she said in an episode that aired on Sept. 20. “Things happened, but that doesn’t just stop me from caring about him or loving him… I’m still, no matter what, his friend, and I care to see if he is alive for the day.”

A rep for E! told FOX411 despite reports the show was not filming Odom's tragedy. 

“Lamar Odom appeared on several seasons of 'Keeping Up with the Kardashians,' as well as two seasons of his own series 'Khloé & Lamar.' We are saddened to hear of his condition, and are sending out thoughts and prayers for his recovery. 'Keeping Up with the Kardashians' is not currently shooting in Las Vegas.”

The two were married in 2009 in a large ceremony that was taped for the E! network, following a whirlwind engagement that was also filmed. The pair married exactly one month after they met. 

He has a daughter, Destiny, and a son Lamar Jr., from a previous relationship. In 2006, Odom's 6-month-old son Jayden died from SIDS while sleeping in his crib in New York.

Odom spent the best years of his career with the Lakers, winning his championship rings and the NBA's Sixth Man of the Year award in 2011. After seven years in purple and gold, the Lakers attempted to trade him to New Orleans in a multiplayer trade for Chris Paul. He eventually went to Dallas in another deal, but was out of the NBA just two years later.

The Lakers played an exhibition game in Las Vegas on Tuesday night, losing to Sacramento. Kobe Bryant and Metta World Peace are Odom's only remaining teammates on the roster.

The New York Daily News reported Bryant had joined the Kardashians at the hospital to be by Odom's bedside. 

Meanwhile, a distraught World Peace briefly spoke to reporters about Odom following Tuesday night's game. 

"There's not one word I could say that would make sense," World Peace told reporters, declining further comment.

Born Lamar Joseph Odom on Nov. 6, 1979, in New York City, he was raised by his grandmother after his mother died of cancer when he was 12. His father was a drug addict.

Some troubles that met Odom before and during his career appeared to worsen after he left the league, and included a no-contest plea to drunken driving shortly before his divorce.

Odom was suspended during the 2000-01 season for violating the NBA's anti-drug policy for the second time in eight months. During the 2010-11 season, a cousin he was close to died and Odom was a passenger in a vehicle involved in an accident in New York that killed a cyclist.

His longtime best friend, who frequently appeared on "Khloe and Lamar," Jamie Sangouthai, died in June after he contracted a flesh-eating bacteria from dirty needles. Later that same month, his friend Bobby Heyward died of a drug overdose.

In the Oct. 3 episode of "Keeping Up With The Kardashians" Khloe Kadashian is filmed speaking with an emotional Odom on the phone following Sangouthai's death.

She tells the cameras following their call, “I’m really on high alert for Lamar, because, I mean, anything, I think, will set him to spiral and that’s kind of the last thing I want for him.”  

The Associated Press contributed to this report.