Peter Theo Curtis, 45, went missing in 2012 and was held by Nusra Front, al Qaeda's official wing in Syria, whose rivals, the militant group Islamic State, last week killed journalist James Foley. Curtis was released on Sunday.
"He was so excited," his mother, Nancy Curtis, told ABC News in an interview taped on Monday. The two spoke briefly after his release, she said, adding that Curtis was staying in a hotel and even having a beer before heading home.
Curtis arrived in the United States late on Tuesday, US media reported. He landed in Newark on a flight from Tel Aviv and then flew on to Boston, where he was greeted by his mother, the New York Times reported, citing a family statement.
After hearing from her son, Curtis said she immediately wrote to Foley's mother, Diane. Last week, Islamic State released a video showing his beheading and threatening to kill another American journalist being held hostage, Steven Sotloff.
"We've been through so much together, and I didn't want her to hear it from the media first," Curtis said of her son's release, speaking from Cambridge, Massachusetts, on ABC's "Good Morning America" program.
About a month ago, Curtis said the FBI had received a frightening video of her son pleading for his life and saying he had just three days left to live. She has not watched the video, she added.
Curtis' father, Michael Padnos, said the search for his son was like "hunting for bats in a dark, black cave" because he could not communicate with him, according to CBS News.
"It felt as if there was a huge weight lifted from my shoulders," he said of his son's release, speaking from France in an interview that aired on "CBS This Morning."
The comments come against the backdrop of efforts to free other US hostages in Syria. On Monday, sources familiar with the matter said Qatar, whose diplomacy helped free Curtis, is working to help free four other Americans held hostage in Syria by various armed groups.
At the same time, the United States is preparing military options, including surveillance flights, to pressure Islamic State in Syria, US officials say.