Investigation of the influence of EPs® 7630, a herbal drug preparation from Pelargonium sidoides, on replication of a broad panel of respiratory viruses.

The Pelargonium sidoides extract EPs® 7630 is an approved drug for the treatment of acute bronchitis in Germany. The postulated mechanisms underlying beneficial effects of EPs® 7630 in bronchitis patients include immunomodulatory and cytoprotective effects, inhibition of interaction between bacteria and host cells, and increase of cilliary beat frequency on respiratory cells. Here, we investigated the influence of EPs® 7630 on replication of a panel of respiratory viruses. Determination of virus-induced cytopathogenic effects and virus titres revealed that EPs® 7630 at concentrations up to 100 μg/ml interfered with replication of seasonal influenza A virus strains (H1N1, H3N2), respiratory syncytial virus, human coronavirus, parainfluenza virus, and coxsackie virus but did not affect replication of highly pathogenic avian influenza A virus (H5N1), adenovirus, or rhinovirus. Therefore, antiviral effects may contribute to the beneficial effects exerted by EPs® 7630 in acute bronchitis patients.