Cyndi Lauper suffering altitude sickness

Pop star CYNDI LAUPER is battling a bout of altitude sickness after flying in to Utah for the Sundance Film Festival on Friday (18Jan13).

The Girls Just Wanna Have Fun hitmaker is booked to perform at an event for America's AMC and WEtv networks, but she is struggling to overcome an illness as she prepares for the gig.

In a series of Twitter.com posts, she writes, "I'm in Park City, Utah rt (right) now. Going to sing at the AMC/WEtv party tonight. Got a little of that altitude sickness. Trying to eat vegan."

The Sundance Film Festival founder Robert Redford launched the 2013 event on Thursday (17Jan13). The annual bash runs until 27 January (13).