Mullein Leaf has served many purposes over the past few centuries, from making candlewicks to casting out evil spirits. However, as an herbal treatment, Verbascum thapsus was primarily used as a cure for diarrhea, respiratory diseases and hemorrhoids. The leaves and flowers of the Mullein Leaf are classified in traditional herbal literature as expectorants and demulcents. - Mullein Leaf or scientifically referred to as Verbascum Thapsus is a wildflower native to much of Europe and Asia which can grow almost anywhere. Because of its thick, soft leaves, it is also called Grandmother's Flannel and Our Lady's Flannel.