Donald Trump wants Hillary Clinton drug-tested before their next debate, again claiming she should be in prison and that the election is "rigged".
The former Celebrity Apprentice star and Republican candidate for US President has strongly suggested his Democratic rival was using performance-enhancing drugs during their last debate.
"We should take a drug test prior [to the next debate] because I don't know what's going on with her," he told supporters at a rally in Portsmouth, New Hampshire.
"At the beginning of her last debate she was all pumped up at the beginning and at the end it was, 'Huh, take me down.' She could barely reach her car. So I think we should take a drug test.
"We're like athletes. They make them take a drug test. I think we should take a drug test prior to the debate. I think we should - why don't we do that? Anyway, I'm willing to do it."
Mr Trump made no mention of his frequent audible sniffing during the debates, which self-described "cocaine expert" and Star Wars icon Carrie Fisher jokingly claimed on Twitter indicated he'd been using.
Howard Dean, the former Governor of Vermont, was forced to apologise for also tweeting a suggestion the sniffing could be due to cocaine use.
Mr Trump's talk of drug use comes at the end of one of his toughest weeks on the campaign yet, with several women claiming he has sexually harassed them and multiple historical videos emerging that document his inappropriate behaviour.
Responding angrily to the claims on Twitter, Mr Trump claimed it is all lies created to support Ms Clinton, whom he says should be behind bars.
The third and final US presidential debate will take place at 2pm on Thursday, October 20 (New Zealand time).