Reid spokesman Adam Jentleson said in a statement he was hospitalized as a precaution after he said he wasn't feeling well.
"Early this morning, Senator Reid was not feeling well and as a precaution decided to go to the hospital. Tests have been conducted and everything is normal," Jentleson said. "He is alert, resting and feeling better."
Jentleson said Reid, 74, would not be working Friday as doctors had asked that Reid remain hospitalized for observation at George Washington University Hospital in Washington.
ABC News reported Reid was released Friday evening after being treated for exhaustion.
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