Stonefish are the worlds’ most venomous fish, however, these organisms also secrete a poison, termed ichthyocrinotoxin, from wart-like protrusions (i.e. tubercles) within their epidermis. Our study found that stonefish ichthyocrinotoxin was toxic to the infective (L3) larval stage of the rodent hookworm (Nippostrongylus brasiliensis) at all concentrations tested. Synanceia horrida ichthyocrinotoxin, within the concentration range that was found to be toxic to L3 N. brasiliensis, was not cytotoxic to human cardiomyocytes, skeletal muscle cells or bile duct cells. The results of this study suggest that stonefish ichthyocrinotoxins may have potential applications to medical therapeutics, particularly to the development of anthelminthics.