Popping a pill to suppress your fever could make flu season worse for everybody, according to a new Canadian study that estimates fever-reducing drugs lead to more than a thousand influenza deaths across North America every year.
"People don't realize that when they take drugs to make themselves feel better when they have influenza they might actually become more infectious and as a result end up infecting more people," said McMaster University mathematics professor David Earn, lead author of a paper published Tuesday in Proceedings of the Royal Society B.
Spiking a temperature is one of the ways the human body combats a virus. When sick people use medications such as ibuprofen or acetaminophen to bring down a fever, they inadvertently bring down their defences against the flu.
The result? More virus in the body and a higher likelihood of spreading influenza.
Dr. Earn and his co-authors looked at past studies on human volunteers and ferrets – the best animal proxies for flu research – and then used a mathematical formula to conclude that fever-reducing drugs may lead to tens of thousands of extra cases of influenza and more than 1,000 flu deaths across North America every year.
Dr. Earn, who is also an investigator at McMaster's Michael G. DeGroote Institute for Infectious Disease Research, called those figures conservative.
For example, he and his co-authors did not have the data to take into account how sick people behave after their fevers come down.
If they feel better, they are likelier to get out of bed and give their family and friends the flu, Dr. Earn said.
He is urging Canadians not to make that mistake this flu season. "Don't go to work or school because you feel better after you took the medication. Stay home."