Oscillococcinum is a patented homeopathic product manufactured by Boiron Laboratories, made from the heart and liver of wild duck. Homeopathic products are extreme dilutions of active ingredients, often so diluted that they dont contain any active medicine. The basic principles are "like treats like" and "potentiation through dilution." For example, the flu would be treated with an extreme dilution of a substance that causes flu-like symptoms. People use oscillococcinum for symptoms of the common cold and flu, but there is no good scientific evidence to support these uses. Homeopathic products have been permitted for sale in the US since 1938, but they are not held to safety and effectiveness standards the way that conventional medicines are.

In summary, Oscillococcinum is a homeopathic product made from the heart and liver of wild duck, used by some people to treat symptoms of the common cold and flu, but there is no good scientific evidence to support these uses.