My son had eight plantars warts on his feet from being around a swimming pool all the time (he now religiously wears sandals as much as he can). Anyway, we started using the castor oil/baking soda and it was working. Then I decided to try Colloidal Silver (90%) and DMSO (10%) on the warts and they were gone within a week. It was absolutely amazing. This would probably be a better choice with an open sore because the silver is antibacterial as well as antiviral. I used Colloidal Silver that I made myself that came out really strong but you can buy it at health food stores.