Five patients had a neurological syndrome develop beginning three to ten days after Hymenoptera insect stings. Three had typical acute inflammatory polyradiculoneuropathy (Guillain-Barré syndrome). A fourth was similar, except that seizures developed, and the fifth patient showed only cranial nerve involvement and hyporeflexia. The timing of these neurological manifestations following insect stings suggests the possibility of a direct or indirect cause-and-effect relationship. (JAMA1982;247:1443-1445)