"All this stuff has been dragged out, and not one example -- not even one -- of something wrong has been cited," the former president said in an at-times contentious interview with Charlie Rose aired Monday night on PBS.
"But millions of dollars have been spent, and look what you're doing, Charlie," Clinton said, criticizing Rose's line of questioning.
Hillary Clinton's departed early from a commemorative ceremony at Ground Zero in Manhattan on Sunday, and a video revealed her wobbling before stumbling as she was assisted into her campaign van. Her campaign revealed hours later Sunday that she'd been diagnosed Friday with pneumonia, and said she'd become overheated that morning. Bill Clinton said nothing more serious is happening.
"Well, if it is (more serious) then it's a mystery to me and all of her doctors," Bill Clinton said, adding that similar instances have happened from time to time.
But Clinton also offered a robust defense of his charitable foundation. And he said he plans to step down from it's board of directors if Hillary Clinton wins in November, and that the foundation will stop accepting foreign and corporate contributions then as well.
Asked why he won't make those moves now, before November 8, Clinton said: "Because there is nothing wrong with what we're doing now and because I've got to wind it down. Because it takes time to undo this -- we've got a lot of lives on the line."
The Clinton Foundation funds and operates a long list of worldwide health and climate change initiatives -- including providing two-thirds of the world's HIV/AIDS treatment access.
"We have been as transparent as we can be, and we've been more transparent than any other foundation -- more transparent than any other foundation has been asked to be, and certainly more transparent than anybody else in this line of work," Clinton said.
"I have said, to the best of my knowledge, nobody ever got anything from the State Department because they supported the Clinton Foundation," he said. "If they did and it was inappropriate, I would say that was wrong, too."
Bill Clinton blamed voters' lack of trust in Hillary Clinton -- including polls showing three-in-five Americans say she isn't trustworthy -- on Republicans for their allegations that the Clinton Foundation's donors had enhanced access to Clinton during her tenure as secretary of state in President Barack Obama's first term.
"There's never been a foundation to disclose as much as I have," he said. "Then why don't people feel trust? Because of the way the disclosed information is selectively used."
Clinton said if Hillary Clinton is elected president, the foundation will continue operating his presidential library, working on community health and operating the Clinton Global Initiative for university students.
That, he said, can be done through individual contributions and donations from charitable organizations like the Carnegie Foundation.
"I don't know what the future will bring, but we need to be transparent ... and we need to recognize that if she is the president, there is the possibility of conflict," Clinton said.
Asked what the Clinton Foundation's most important achievement has been, Bill Clinton said: "We got the world's cheapest AIDS medicine to more than half the people on earth who are alive with it, including more than two-thirds of the kids.
"We built an organization that helped 430 million people in 180 countries just by getting people together, including organizing the first 500 tons of medical equipment to the Ebola epidemic, and it didn't cost the taxpayers a penny. And we made life better for a lot of Americans.
"We created jobs and saved lives. I'm proud of that. We got caught trying," he said.