The rapper posted several photos on the micro-blogging site, including one with a collection of cuddly toys.
"I'm feeling better today I think I'm gonna get out of the hospital soon," he wrote.
50 Cent's friend and collaborator on the upcoming Lost Tape mixtape DJ Drama stated that he has a "stomach virus".
DJ Drama told XXLMag: "First they wanted to keep it quiet, but he's not a quiet guy. He should be cool. It's nothing that serious."
However, a source told People that the hospital trip may in fact be a publicity stunt for the release of the mixtape next week.
The Lost Tape will be released on Tuesday, May 22.
50 Cent is scheduled to release his currently untitled fifth studio album on July 2.