The antimicrobial effect of a cream containing extracts of African geranium (Pelargonium sidoides DC.), black elderberry (Sambucus nigra L.), and St. John’s wort (Hypericum perforatum L.) in colloidal nanosilver (AgNPs) at a concentration of 30 ppm, denoted as SILVER STOP® cream (SS® cream), was examined in vitro. The research was performed with Escherichia coli (ATCC and two clinical isolates), Staphylococcus aureus (ATCC and two clinical strains), and Candida albicans (ATCC and two clinical isolates). The results showed successful healing of the diseases and a very good curative effect of the cream.