Ray J was hospitalized the morning after his appearance at the 2012 Billboard Music Awards on May 20.
The 31-year-old singer's spokesperson confirmed the news to CNN. The spokesperson said Ray J was still in the hospital "and will remain there for treatment for exhaustion and jet lag."
The spokesperson also denied that alcohol or other substances were involved with his hospitalization. Ray J was also in Las Vegas, where the Billboard Awards was held, to host a party for Prince Reigns Hair Serum.
The singer recently returned stateside from a trip to China where he performed a concert. He Tweeted on May 17 that he was in Hong Kong.
TMZ was the first to report about Ray J's hospitalization, reporting that the singer was upset about an alleged confrontation he had with Whitney Houston's sister-in-law, Patricia Houston, at the ceremony. Prior to Whitney Houston's death on February 11, Ray J was rumored to be dating the star.
In a February interview for his new book "Death of the Cheating Man," Ray J did not confirm whether the two were ever romantically involved but said he had "a lot of love" for the singer.
"I've been knowing her for years and years and years," Ray J said about Houston in an interview taped before the signer's death. "When we go out it's just, the next day it's everywhere and there's so many different stories but that's my people, that's my friend."
At the 2012 Billboard Awards, Houston was honored with the Millennium Award, which was accepted on her behalf by Patricia Houston and Whitney Houston's daughter Bobbi Kristina Brown.