Lady Gaga hospitalized in Denver for altitude sickness

Spending the last six years on the highest of high heels did not prepare Lady Gaga for her performance in the Mile-High City. The “G.U.Y.” singer was hospitalized for altitude sickness following her artRAVE: The ARTPOP Ball show in Denver, Colo. last night.

Gaga, who is currently in the middle of a world tour in support of last year’s ARTPOP, posted a photo to Instagram in which she is seen wearing an (upside-down) oxygen mask. The caption reads “Altitude Sickness is no Joke! #hitThatHospitalSh-t #artRaveDenver many true ravers crowd tonight.”

Why the mask is upside-down remains unclear. Perhaps it is a fashion statement of some kind.

Altitude sickness affects many people in places like Denver, which is, as its nickname suggests, is an entire mile above sea level. Denver’s official website even warns: “Watch Your Physical Activity.” If you’ve ever seen Gaga perform, you know she likely did not heed that advice.

In addition to her tour, Gaga is also preparing to release an album of jazz standards recorded with Tony Bennett. The album, called "Cheek to Cheek," will be released September 23. Listen to the first single, “Anything Goes,” below.

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