Los Angeles: Pop sensation Lady Gaga has been hospitalised for altitude sickness following her concert in Denver, Colorado.
The 28-year-old singer took to Instagram to share a close-up photo of herself wearing an oxygen mask, reportedly.
"Altitude Sickness is no Joke! #hitThatHospital. #artRaveDenver many true ravers crowd tonight," she wrote along with the picture.
This is not the first time Gaga was hospitalised. Back in April, the `Poker Face` hitmaker underwent an operation to extract her wisdom teeth.
Gaga`s next gig in Seattle, as part of her `ArtRave: The Artpop Ball` tour, is still scheduled to go on as planned.