"She had fainted and was out cold," a source told the magazine. "It was scary."
The incident at the Fendi fashion show occurred while Stone, 54, was in town for a benefit for the AIDS research foundation amfAR.
"Sharon experienced migraine related symptoms, and we all felt it best that she got checked out before the amfAR event," a representative for the organization told the magazine. "She was examined and given a clean bill of health. And as she said, wild horses couldn't keep her away."
The magazine said Stone was at the fashion show with her 27-year-old Argentine boyfriend Martin Mica.
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