A supercritical fluid (SCF) extract of a cardiac glycoside-containing plantmass is provided. The extract can be included in a pharmaceutical compositioncontaining an extract-solubilizing amount of solubilizer. Oleandrin isincluded within the extract when a cardiac glycoside-containing plant, such asNerium oleander, is extracted by SCF extraction. The extract can also containone or more other SCF extractable pharmacologically active agents. Thecomposition can be used to treat a wide range of disorders that aretherapeutically responsive to a cardiac glycoside.