'Something funny was going on': Howard Dean defends his bizarre theory alleging Trump uses cocaine

Donald Trump's repeated sniffling throughout Monday night's debate set social media ablaze as viewers wondered if it was a nervous tick, allergies, or a cold.

Former Vermont governor and 2004 presidential candidate Howard Dean had a different theory, however:

Dean's tweet quickly went viral, racking up more than 26,000 retweets by Tuesday afternoon.

Donald Trump told Fox on Tuesday morning that he wasn't sniffling and that he does not have a cold. Still, Dean defended his hypothesis on MSNBC on Tuesday.

"Well you can't make a diagnosis over the television, but that [the sniffling] is a signature of people who use cocaine," Dean said. "I'm not suggesting that Trump does, but-."

MSNBC reporter Kate Snow interjected, noting that Dean made the suggestion in his tweet.

"I'm just suggesting that we think about it," Dean replied. "He sniffed during the presentation, which is something that [cocaine] users do. He also has grandiosity, which is something that accompanies that problem."

Dean said that Trump has "delusions," such as his tendency to flip-flop on issues and think he won't "get caught." 

Dean continued:

"He also has trouble with pressured speech. He interrupted Hillary Clinton 29 times, he couldn't keep himself together. Do I think at 70 years old he has a cocaine problem? Probably not. But it'd be interesting to ask him and see if he ever had a problem with that ... I just was struck by the sniffing and by his behavior."

Snow pointed out that Dean's comments resembled the conspiracy theories floated about Hillary Clinton's health by former New York City mayor Rudy Giuliani, who has speculated about her condition and encouraged people to "Google Hillary Clinton's illness."

Dean said that Donald Trump has not made his medical history public "in any meaningful way."

"Hillary Clinton has done that," he argued.

The former DNC chair added that he didn't find his cocaine theory to be a "ridiculous idea."

"Something funny was going on with Donald Trump last night," he said.

Dean said he will "absolutely" not apologize or delete the tweet. He told Snow he stands by his charges and said Trump needed to answer them.