St. John's wortListen to pronunciation(… wort)An herbal product sold as an over-the-counter treatment for depression. It is being studied for its ability to lessen certain side effects of cancer treatment. Also called Hypericum perforatum.More InformationCancer Therapy Interactions With Foods and Dietary SupplementsSearch NCI's Dictionary of Cancer TermsStarts withContainsBrowse:ABCDEFGHIJKLMNOPQRSTUVWXYZ#