Rihanna sick at Portugal show

Rihanna struggled through illness to perform in Portugal on Saturday (17Dec11) and even ran off stage mid-set to vomit.

The Bajan beauty sang her hits to a sell-out crowd at Lisbon's Atlantico Arena, but the audience was left baffled when she disappeared during her performance of What's My Name?

She took to her Twitter.com account after the gig to explain the incident, revealing she was feeling unwell during the concert.

In a series of posts, she writes, "Portugal tonight was legendary!!! I ran off stage to throw up, halfway thru (through) What's My Name... made it back juuuust (sic) in time for Rude Boy."

Rihanna appeared to be feeling better on Sunday (18Dec11) and told fans, "We just had our end of year/tour Christmas party!!!! We turned it into an 80's prom, since I've never had one! It was sooo (sic) much fun!!!! I'm decked out in lace, sequins, a giant bow, and hair spray!!!!!"