Maybe Dr. Luke wasn't the one she needed.

Rihanna tweeted a photo of her arm hooked up to an IV today. She apologized to her Swedish fans, writing, "Sorry Malmo!!!" Ouch!The 'We Found Love' singer abruptly canceled her sold out Loud Tour stop in Malmo, Sweden at around 7PM due to health concerns. No further explanation was given, but based on the IV and the fact that she's healthy enough to tweet, fatigue or dehydration may be the culprit. There's no word yet on if she's still performing in Stockholm, Sweden tomorrow as scheduled.

Guards outside the arena had to thousands of disappointed fans that the concert was off. "It was very sad," a Swedish fan, Natalie Wierenga, told Sydsvenskan. "It could well have [been] communicated earlier."

While we're sure Rihanna didn't plan to fall ill, if she knew she wasn't feeling well, Wierenga is right -- she could have made it clear way before the arena began to fill with eager fans. We hope she feels better, but bailing at the last minute seems hypocritical coming from an artist who sings a song called 'Rude Boy.'

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