Although that is part of the reason, it is actually more complicated than that. As well as dulling pain, the pills also lower the fever. The fever seems to be the body’s way of killing off the virus. So lowering the fever results in more virus, and for longer, allowing sick people to infect even more other people. A triple whammy.
Coincidentally, a letter in the same issue, from Steve Dalton, reminded me of a previous article, about how fever appears to help with some forms of cancer. Dalton wonders whether the fever-reducing drugs are possibly increasing cancers.
I’ve heard before that the fever is the “body’s natural defence” against colds and flu, rather than just being an inconvenient side-effect of our immune response. Are we making a mistake by intervening? Now, I don’t think that “natural” automatically means “better” (smallpox, cholera and polio are all natural, after all), or that “unnatural” (whatever that even means) is worse. But I do know a bit about complex systems, non-linear responses, and the law of unintended consequences, and that “but it’s more complicated than that” is the rule, not the exception.
So, before my next cold arrives: are there any cold remedies that just kill the pain, and don’t reduce the fever?
UPDATE (1 Feb 2014): a colleague says that codeine fits the bill. But we agreed that it’s not really a viable solution, given that it’s prescription-only, and seems a bit like overkill for a cold.