Fully ripe fruits can be eaten raw in moderation. The powdered rhizomes have a potent laxative effect. The rhizomes also contain potent anticancer substances, and a derivative of one of these is used to tret human cancers. But extracts of the rhizomes are much too poisonous to be used for self-medication. Mayapple is listed in the U.S. Pharmacopeia.
All parts except the ripe fruits are poisonous.