Secretary of State Hillary Rodham Clinton was discharged from a New York City hospital Wednesday evening after three days of treatment for a potentially dangerous blood clot in her head, the State Department said.

“Her medical team advised her that she is making good progress on all fronts, and they are confident she will make a full recovery,” according to a statement released by Clinton aide Philippe Reines. “She’s eager to get back to the office, and we will keep you updated on her schedule as it becomes clearer in the coming days.”

The brief statement, after a series of medical setbacks that kept the nation’s top diplomat out of public view for more than three weeks, did not say when Clinton would be back to work.

She had appeared briefly outside New York Presbyterian Hospital-Columbia University Medical Center earlier in the day, accompanied by her husband, former president Bill Clinton, and their daughter, Chelsea, but then returned inside. The appearance, photographed by Reuters, was apparently a brief foray related to her subsequent discharge.

In Twitter messages, Chelsea Clinton said her mother was “headed home,” presumably to the family home in Chappaqua, N.Y., and expressed gratitude to the medical staff “for taking great care of my Mom.”

The State Department had released little new information about Clinton’s health after a statement Sunday saying that she had been hospitalized after an MRI scan revealed a clot. It was not until Monday that her doctors issued a statement saying the clot was in a vein behind her right ear.

The doctors, Lisa Bardack of the Mount Kisco Medical Group and Gigi El-Bayoumi of George Washington University, said Clinton had suffered no neurological damage or stroke and was being treated with blood thinners. They did not indicate what caused the clot, which was discovered after she contracted a stomach virus during a trip last month to Europe. On Dec. 15, the State Department said she had also suffered a concussion from a fall after fainting from virus-related dehydration.

Clinton’s lengthy absence clouds the closing days or weeks of a widely respected tenure as secretary of state and has fed speculation about the severity of her illness. The unusual health scare ensures that she would be questioned closely about her fitness should she run for president in 2016.

Victoria Nuland, a spokeswoman for the State Department, said before Clinton’s discharge that the secretary had been making phone calls, including on Wednesday.

“She has been talking to her staff, including today,” Nuland said. “She’s been quite active on the phone.”

Speculation about the severity of Clinton’s condition has grown over her long absence and has migrated beyond conservative media sites and commentators who initially accused her of faking her illness to broader questions about whether she is much sicker than her doctors’ statement suggested.

“I think really we’ve been extremely forthcoming, including from her doctors, on the very specific issues here,” Nuland said. She had earlier called the charge of fakery baseless.

Location of Hillary Clinton's blood clot.

There is no standard for how much information the public is owed about the health of a sitting Cabinet secretary. Clinton’s absence has had no measurable effect on diplomacy, although she canceled an overseas trip and two congressional appearances. Clinton is not an elected official, like the president, whose health is scrutinized closely. Recent presidents have routinely released summaries of their annual checkups, but other government officials do not.

Nuland said that on Saturday, before the clot was diagnosed, Clinton spoke to the United Nations envoy for Syria, Lakhdar Brahimi, about his recent meeting with embattled Syrian President Bashar al-Assad. Clinton also called Qatar’s prime minister, Nuland said.

Information on Clinton’s condition has come from her office in dribbles, beginning with the Dec. 10 cancellation of a planned Mideast trip.

Uncertainty about her condition left unclear whether she would keep her promise to testify to Congress about the report of an independent panel that found severe shortfalls in State Department security and planning ahead of the fatal Sept. 11 attack on a diplomatic compound and CIA station in Benghazi, Libya.

Clinton remains committed to testifying, a State Department official, speaking on the condition of anonymity to discuss the secretary’s health in greater depth, said this week. No dates for her testimony have been announced. Some Republicans have threatened to hold up confirmation of Sen. John F. Kerry (D-Mass.) as her successor.

Although no date for Kerry’s confirmation hearing has been announced, the White House had hoped that his nomination would move quickly through the Senate in January. Clinton had long said that she planned to stay only through President Obama’s first term. He selected Kerry as her replacement on Dec. 21.

Clinton had canceled appearances before the Senate Foreign Relations Committee and the House Foreign Affairs Committee on Dec. 20 because of the concussion. She sent deputies in her place and promised to testify in person in January. That was mostly a gesture to House Republicans, some of whom have accused the administration of duplicity in explaining the origin of the Benghazi attack and the administration’s response.

The incoming chairman of the House Foreign Affairs Committee, Rep. Edward R. Royce (R-Calif.), had said that he wanted to hear from Clinton directly. When the Accountability Review Board’s findings of security lapses were released, Royce said they pointed to an unacceptable failure of leadership.

“Looking to the next Congress, the House Foreign Affairs Committee has much work to do to dig deeper and correct the management deficiencies at the State Department to make our diplomats more secure,” Royce said.