The 48-year-old governor, who uses an inhaler for asthma and is overweight, was taken to Somerset Medical Center around 10:30 a.m. Thursday. The blunt-talking governor, who some Republicans have been trying to persuade to run for president, was headed to a bill signing event when he felt unwell.
Christie told reporters as he left the hospital that he woke up in the morning not feeling great and his rescue inhaler didn't work as well as it normally does. He says he thought about his kids and decided it would be best to go to the hospital.
His wife, Mary Pat, went to the hospital, but left after a few hours to attend their son's baseball game. The Christies have four children.
Christie said doctors performed an EKG, blood work and chest X-ray and all came back normal.
"I'm a little tired. Other than tired, I feel fine," Christie said.
Christie said he was heading home to rest and see his daughters. He canceled his monthly "Ask the Governor" radio show, which was scheduled for Thursday night. He has no public schedule for Friday, but said he planned to be at the Statehouse on Friday for staff meetings.
The last time Christie sought emergency treatment for asthma was when he was in law school, spokesman Michael Drewniak said.
Christie, a former federal prosecutor who took office 18 months ago, has drawn praise from fiscal conservatives and complaints from unions for efforts to trim benefits for public employees as part of steep budget cuts. His national profile also has risen, in part, for his frank and sometimes confrontational exchanges with the media.
The governor attended an education conference and a congressional fundraiser in Iowa on Monday, where he again told reporters he was not running for president. He has said that his four school-age children and further goals in his first term rule out a White House bid, but Republicans continue to court him.
The governor has made headlines for his sometimes stormy relationship with Democratic lawmakers.
Senate President Stephen Sweeney recently called Christie a "bully and a punk" after the governor cut $1.3 billion from the state budget Democrats had sent him. But on Thursday Sweeney issued a statement wishing the governor a speedy recovery.
"Politics goes out the door at a time like this, and I join all of New Jersey in wishing the governor well and hoping for his swift return," Sweeney said.
Christie has been open about some of his health problems.
He has long struggled with his weight, which he said he started putting on after high school when he stopped playing organized sports. He's tried dozens of diets over the years with varying success and has shed some pounds in recent months.
His weight came up during his 2009 campaign against Democrat incumbent Jon Corzine, who ran an ad accusing Christie of "throwing his weight around" to get out of traffic citations while he was U.S. attorney. Christie confronted the ads head on, telling Corzine to "man up and say I'm fat."
In April, Christie told a town hall meeting in Hamilton, "I'm an asthmatic and I take an inhaler every morning."
Christie was named the state's top federal law enforcement officer after playing an important role in President George W. Bush's 2000 campaign in the state.
He soon gained national exposure by overseeing two major terrorism convictions and the convictions of dozens of public officials on corruption charges.
Christie's hospitalization lit up Twitter, with some people offering well wishes and others ridiculing him for his weight, trying to connect it to his asthma.
Conservative commentator Ann Coulter, who supports a Christie presidential run, made light of the situation.
"I took Christie's inhaler away until he promised to run in 2012," she tweeted.
Christie personally joined in from his hospital room, taking to Twitter to thank Democratic state Sen. Barbara Buono, a frequent critic, for her get-well wishes: "Thx 4 your kind thoughts...and BTW, Happy Birthday!"
DeFalco reported from Trenton, N.J. Associated Press writer Josh Lederman in Trenton contributed to this report.