Echinacea and the common cold–Myth vs. Science

It’s getting close to winter once again, so people always recommend their various lotions and potions to either prevent the common cold or, at least, to reduce the course of the disease. Alternative medicine’s favorite disease to treat is the common cold, mainly because it’s an easy disease to handle without too many serious problems. Also, from the patient’s perspective, the length and seriousness of the cold is usually very subjective, since the patient has a difficult time making an accurate determination when the cold started or ended, and making a quantitative assessment of the seriousness of the disease. Moreover,  confirmation bias is usually the reason one hears that something worked for the cold–the person who reports some product works forgets all the times it doesn’t. Or completely misjudges the actual effects of any treatment.

The list of products that you might run across in your local pharmacy that claim to have an effect on the common cold are many. Zinc, oscillococcinum, garlic, and vitamin C. I wrote about these products last winter, and they mostly don’t work. The strangest cold remedy you might find is oscillococcinum, which is a homeopathic preparation derived from duck liver and heart, diluted to 200C, or 200 1:100 dilutions.  In other words, in a liter of water there are precisely no molecules of duck guts. And there isn’t any logical explanation of a possible mechanism that would allow one to conclude that duck offal has an effect on cold viruses. Though Oscillococcinum is supposed to be used for flus, many use it for colds, but it doesn’t matter, why would a diluted potion of duck guts cure any virus? Well, Cochrane Reviews concluded that ”current evidence does not support a preventative effect of Oscillococcinum-like homeopathic medicines in influenza and influenza-like syndromes.Continue reading “Echinacea and the common cold–Myth vs. Science”