Ask the Doctors by Eve Glazier, M.D. and Elizabeth Ko, M.D

Oscillococcinum's Effectiveness as Flu Treatment Is Inconclusive

Dear Doctor: Does Oscillococcinum work as a flu treatment?

Dear Reader: Oscillococcinum is a homeopathic preparation. Unlike the sound of the name, it has nothing to do with bacteria. The product is derived from wild ducks' hearts and livers. In a homeopathic method, that extract is diluted up to 200 times, such that a miniscule amount of the material is in the final product. The belief is that the heart and liver of a wild duck may have influenza virus and that diluting this material may somehow cause an increased immune response to the flu.

But no studies have shown that Oscillococcinum causes any specific alteration to the influenza virus or the immune system.

However, studies have looked at Oscillococcinum for the prevention and treatment of influenza. A 2015 study reviewed six trials. Two trials assessed the use of Oscillococcinum for prevention of influenza and four trials assessed its use for treatment. The two prevention trials, with a total of 327 people, found a 52 percent decrease in influenza risk among those who used Oscillococcinum.

Out of the four treatment trials, two of the trials -- with a total of 796 participants -- found an 86 percent greater chance that symptoms would resolve after 48 hours among those who took Oscillococcinum compared to those who didn't. (This isn't a dramatic difference when you consider the absolute numbers. To be precise, it amounts to a 16.7 percent chance of resolution in the Oscillococcinum group and a 9 percent chance of resolution in the placebo group.) One interesting note is that patients ages 12 to 29 were much more likely to report a positive effect than those over 30.

After three days, however, the difference between the placebo group and the treatment group declined, and by the fourth day there was no difference. Of further note, there was a 39 percent reduction in the use of other influenza medications in the group that took Oscillococcinum.

The two other studies in this review looked at a physician assessment of patients 48 hours after the onset of symptoms, and while there was a mild improvement seen with the preparation, it was not statistically significant.

Note that the authors of the review found multiple flaws in the methodology of the studies and said that the studies were potentially biased. Thus, they were not convinced of the benefits of Oscillococcinum for either the prevention or treatment of influenza.

A 2009 and 2012 review of multiple studies showed a mild benefit toward Oscillococcinum, but these studies also were considered of poor quality, and the authors could not make any conclusion about the benefit of the medication.

As for whether Oscillococcinum works, I know it isn't satisfactory, but the answer is "maybe." Better-quality studies are necessary. One good thing about the prior studies was that there was little difference between the medication and placebo regarding side effects, so if you take it, it should be safe.

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