Dr Bennet Omalu, the doctor who exposed the NFL concussion crisis, tweeted: ‘I must advice (sic) the Clinton campaign to perform toxicologic analysis of Ms Clinton’s blood. It is possible she is being poisoned.’
He then went on to add: ‘I do not trust Mr Putin and Mr Trump. With those two all things are possible.’
Dr Omalu was played by actor Will Smith in the recent film Concussion, which tells how he diagnosed serious health consequences with retired NFL footballers in the United States.
He made the link between concussions sustained playing American football and a long-term brain disorder – chronic traumatic encephalopathy – despite denials from the NFL.
The Republican presidential candidate Donald Trump has not reacted to Dr Omalu’s tweets but he has wished Mrs Clinton well and said he hoped to see her at the first televised presidential debate on September 22.
Clinton suffered two coughing fits while on the campaign trail, one while she was speaking publicly in Ohio and another while she was taking questions from reporters.
In December 2012 Clinton fainted and suffered a concussion after contracting a stomach virus. She later developed a blood clot.
She has been taking the anticoagulation drug, Coumadin, ever since.
In 2005 she fainted before a scheduled speech in Buffalo, New York, after suffering a similar stomach virus.