Dallas fans were enjoying the Kings of Leon show on Friday night when suddenly lead singer, Caleb Followill said that he needed to take a breather for a minute backstage to throw up and drink a beer. After promising to return in a few moments and play three more songs, Followill never did return to the stage and the concert was ultimately cancelled.

To clear up any rumors that were beginning to spark, Followill made it clear that he was not drunk, he was just hot; and it’s not hard to see why. While running around on-stage and singing his little heart out, the temperature was in the high 90s that night and the band was performing in an outdoor venue at the Gexa Energy Pavillion. It was found later that not only was Followill suffering from heat exhaustion, but also that the temporary condition had caused his vocal chords to seize.

The band was also set to play the following night but that show was cancelled as well. Later, Jared Followill, the band’s bassist, took to Twitter with deep apologies and to say that the cancellation of the two shows were due to more than just illness in the band. Friday’s show has been rescheduled for September 21, 2011, while Saturday’s show is set for the following evening on September 22, 2011.

Update: The Kings Of Leon have cancelled the remainder of the tour for 2011. They have cited that Caleb is suffering from vocal issues and exhaustion but comments from band members make us believe that Caleb, the lead singer, needs substance abuse help.