Gina Talamona of the Justice Department told reporters the 67-year-old Mukasey, who had been rushed to George Washington University Hospital after the attack late Thursday, was recovering, was alert and was anxious to get back to work.
"There's no indication that he suffered a stroke or any heart-related incident," Talamona said outside the hospital. "It really appears to be a fainting spell."
A senior Justice Department official, speaking on condition of anonymity, said that an MRI was clear. The official was not authorized to publicly speak about Mukasey's medical procedures.
Talamona noted that Mukasey had had a very busy day before going to a Washington hotel to give the keynote speech to at a black-tie dinner of The Federalist Society, a conservative-oriented legal group. During the talk, he began to slur his words, nodded, turned and started to collapse when he was caught by men standing nearby.
His spokeswoman noted that he had appeared "under hot lights" and that he keeps a hectic schedule.
She said doctors were doing an additional round of routine tests.
"He certainly wants to leave and get back to work as soon as possible," Talamona said.
Of Mukasey, she said: "He's in good shape, he's very active, he's very alert and very ready to leave."
Mukasey did not transfer his authority as attorney general at any juncture, Talamona indicated. She told reporters that Deputy Attorney General Mark Filip was to go to the hospital to brief Mukasey on departmental matters later Friday morning.