By Adam Levine

Secretary of State Hillary Clinton is "on the mend" and working from home, the State Department’s spokeswoman said Tuesday.

Clinton had been recovering from a bout of stomach flu last week when she fainted and ended up with a concussion. Clinton informed the Senate Foreign Relations and House Foreign Affairs committees this weekend that she would be unable to testify at upcoming hearings about the deadly events in Benghazi, Libya, at the advice of her doctors. In her place, deputies Thomas Nides and Bill Burns will testify on Thursday.

Clinton was finishing her cover letter to Congress to accompany the independent Benghazi review that was just completed, as she recuperates at home from her concussion injury and stomach virus, spokeswoman Victoria Nuland told reporters.

The classified version of the independent review is being sent to Congress Tuesday afternoon, and an unclassified version could be released for public consumption as early as Wednesday, the same day that former Ambassador Thomas Pickering and former Chairman of the Joint Chiefs of Staff Adm. Mike Mullen, who led the review, brief congressional committees about their findings.



Nuland said that it was "completely untrue" that Clinton was using her illness to avoid testifying this week about Benghazi, allegations made in the New York Post opinion page and on Fox News by former U.N. Ambassador John Bolton.

"She's going to be absolutely fine. She is working at home," Nuland said. "She's been on the phone and in e-mail contact with senior staff. She's been working on other issues - Syria, the DPRK [North Korea] today. These are people that don't know what they are talking about."

In a statement from Clinton's doctors released over the weekend, Clinton was told to "rest and avoid any strenuous activity." The doctors said the "strongly advised her to cancel all work events for the coming week."

Typically, a concussion will lead to doctors’ ordering “brain rest,” said Dr. Sanjay Gupta, CNN’s chief medical correspondent.

"You almost want to give the brain rest as well. Doctors will literally say don't read anything, don't watch television, don't get on a computer. You really want to put the brain to rest for a while to allow the brain to recover from a concussion," Gupta said. "The best way to get recovery, full recovery, from a concussion is to really not do anything."

Gupta said the fact Clinton is at home, and not the in the hospital, suggests the nature of the injury may not be too severe.

"I think they obviously would have a low threshold for having her in the hospital. In this case, she's not. So I think the antenna is lowered here," Gupta explained over the weekend.

Gupta, a neurosurgeon, guessed that recovery would take about a week, though he was not privy to her specific case.

"What you want to do is you slowly reintroduce activity, you know, allow someone to start reading, maybe engaging in some exercise, and seeing if any of those symptoms come back. If they come back, then, you're sort of back on rest again. So, it can be back and forth for a little bit. My guess is a week. That's typical with a mild concussion," he said.

Nuland said Tuesday that Clinton’s doctors “and all the people close to her are trying to encourage her to take the time she needs to be well.”

In a letter to the Senate and House foreign affairs committees, Clinton said she "looks forward to continuing to engage them in January, and she will be open to whatever they consider appropriate in that regard," Nuland said earlier this week.