Hillary Clinton on Monday sought to control the fallout from a media swirl around her health after she wobbled away from a 9/11 ceremony and her campaign said she had pneumonia.

The incident on Sunday raised questions drummed up by Republicans in recent months over her health and a purported penchant for secrecy and lack of transparency.

"People get pneumonia all the time," Republican Senator Roger Wicker of Mississippi said in an interview with the Politico news blog, adding, "It is absolutely a natural impulse of her staff to dissemble and lie, and it is just astounding."

Clinton's campaign said Monday it would release new medical records in order to quell any concern over the Democratic president candidate's physical ability.

The 68-year-old fell sick at a 9/11 memorial event in New York on Sunday and a video showed her being helped into a van.

Her campaign first said she "overheated," then her doctor disclosed the former secretary of state had been diagnosed with pneumonia the previous Friday.

Clinton told CNN on Monday that she had ignored her doctor's advice to get five days of rest because she "didn't think it was going to be that big a deal."

Asked if she passed out, Clinton said she did not.

"I felt dizzy and I did lose my balance for a minute, but once I got in (the van), once I could sit down, once I could cool off, once I had some water, I immediately started feeling better," Clinton said.

In the same interview, Clinton hit back at criticism over her lack of transparency by blasting her Republican opponent for declining to release his tax returns - a long standard move during US presidential campaigns.

Clinton also said she would be back on the campaign trail in "next couple of days" after cancelling her attendance at two events in California on Monday and Tuesday and another in Wednesday in Nevada. Former President Bill Clinton will take her place in Nevada.

Commenting on Clinton's health, Donald Trump wished his rival a quick recovery.

"Something is going on but I just hope she gets well and gets back on the trail, and we'll be seeing her at the debate" on September 26, Trump told Fox News.

Trump's running mate, Mike Pence, said the billionaire would also be releasing his medical records in the coming days.

(DW)