Sen. Edward Kennedy was awake and talking with friends, Tuesday afternoon, but will remain in the hospital overnight for observation, officials said.
Kennedy was rushed to the hospital after a seizure during the luncheon following President Barack Obama's inauguration. He was able to talk to Obama on the phone shortly after being checked in.
"After testing, we believe the incident was brought on by simple fatigue," Dr. Edward Aulisi, chairman of neurosurgery at Washington Hospital Center said in a statement.
Obama began his speech at the luncheon voicing his concern for Kennedy, who has suffered seizures in the past because of a brain tumor.
"I would be lying to you if I did not say right now a part of me is with him," Obama said
Former Vice President Walter Mondale was sitting at the table with Kennedy when he saw that the 76-year-old looked very uncomfortable.
Sen. Jay Rockefeller said Obama rushed to the table after he noticed something was wrong.
"There was a call for silence throughout the room," he said. "The president went over immediately. The lights went down, just to reduce the heat, I think."
Sens. Orin Hatch and John Kerry helped Kennedy to the ambulance.
"It looked like a seizure," Hatch told reporters.
Sen. Chris Dodd saw Kennedy as he was put into the ambulence and quoted the senator as saying, I'll be OK, I'll see you later."
"It took a lot out of him. Seizures are exhausting," Dodd said. "The good news is he's gonna be fine."
Around 3 p.m., Mondale said the senator was doing much better. A spokeswoman at the Washington Hospital Center said he was awake and answering questions.
Kennedy was diagnosed with brain cancer about 9 months ago and went through surgery and treatment as a result. He suffered a seizure in September after a change in medication.
Outside of Tuesday's inauguration appearance, Kennedy has also shown for Senate votes and spoke at the Democratic National Convention last August.
Sources: CBN News, The Associated Press, CNN