Properties and Uses:The herb (especially the root) is a relaxing diaphoretic, antispasmodic, carminative, and expectorant. Specially of use in infections of the respiratory tract where there is dampness, such as pleurisy (water in the lung). This is much like another herb in this family, Pleurisy Root (Asclepias tuberosa). Powdered roots used as a poultice on open sores. Dried leaves are preferred because fresh leaves may cause nausea and vomiting.