Lady Gaga shares oxygen mask selfie after being hospitalised with altitude sickness

The singer was in Denver, Colorado, as part of her artRave: The Artpop Ball world tour

Lady Gaga has been hospitalised with altitude sickness... but she's okay (Lady Gaga/Instagram)

Denver, Colorado, also known as the ‘mile-high city', is situated at 5,280ft above sea level with an intermediate altitude that has put Lady Gaga in hospital.

But fans should fear not, she's ok. The Born This Way singer yesterday managed to post a photograph of herself, fake eyelashes and all, attached to an oxygen mask.

She told her fans: “Altitude Sickness is no Joke! #hitThatHospitalShit #artRaveDenver many true ravers crowd tonight.”

Gaga, 28, was in the city for her artRave: The Artpop Ball studio tour on Wednesday.

Though the pop starlet was left needing treatment, she didn’t look too under the weather thanks to a face full of make-up.

It doesn’t look like she was incapacitated for too long, either, soon telling her followers that she was back on the road heading for Seattle.

We're not sure if Gaga partied the night away but for anyone heading to Denver anytime soon, the city offers a number of tips to deal with the change in air.

“In Denver's rarified air, golf balls go ten percent farther... and so do cocktails. Alcoholic drinks pack more of a wallop than at sea level. It is recommended that you go easy on the alcohol in the mountains and in Denver, as its effects will feel stronger here,” Visit Denver says.