Unlike oyster mushrooms, O. nidiformis is poisonous; while not lethal, its consumption leads to severe cramps and vomiting. The toxic properties of the mushroom are attributed to compounds called illudins. O. nidiformis is one of several species in the cosmopolitan genus Omphalotus, all of which have bioluminescent properties.
O. nidiformis differs from edible oyster mushrooms in its toxicity; however, it possesses illudin compounds that induce severe gastrointestinal symptoms upon ingestion. The Omphalotus genus encompasses several bioluminescent species, including the poisonous O. nidiformis.