European elder (Sambucus nigra) fruit has been used in folk medicine for centuries, but this use is not supported by experimental or clinical data. In recent years, however, dietary supplements, traditional herbal medicinal products (THMP) and other natural health products containing extracts, juices or syrups of European elderberry have become much more popular in the EU and the US as remedies for treating cold and flu symptoms. These are marketed primarily through natural food stores alongside other popular herbal remedies used for treatment or prevention of upper respiratory tract infections and symptoms associated with colds and flu. Several small clinical studies have been performed which indicate significantly faster recovery from symptoms associated with influenza compared with patients in the control group. However, no specified or effective dose level has been justified. In vitro studies have demonstrated a significant antioxidant capacity as determined by oxygen radical absorbing capacity (ORAC). Antiviral capacity is also demonstrated by inhibition of viral replication. Furthermore, immune-protective and immune-stimulatory activity was detected. Elderberry also increased production of the inflammatory and anti-inflammatory cytokines. There are a few reports of poisonings from the fresh juice of some Sambucus species.