This report describes the first known case in the literature of acute exposure to a mixture of spinosad and flonicamid that resulted in a substantial clinical toxicities. An 80-year-old depressed female attempted suicide by drinking a mixture of 80-mL Conserve (Dow AgroSciences, Taipei, Taiwan) and 2-3 gram powder of flonicamid (Ishihara Sangyo Kaisha, Taipei, Taiwan). Spinosad was the main compound ingested. The clinical manifestations were mostly neurological, i.e. consciousness disturbance, shock, respiratory failure, pneumonitis and urinary retention. Endoscopic examination found grade 2a corrosive esophageal injury. After resuscitation, detoxification procedures and intensive care, the patient recovered fully without leaving any chronic sequels. An emerging question arising from this report is, why are the clinical symptoms so severe, given that both compounds were claimed safe in laboratory animals? The answer is unclear. One possible explanation is, the amount of spinosad ingested was far beyond the physiological safety dose that can be handled by human body. Other potential contributors to the clinical toxicities in this patient are the solvent compositions that were found in the Conserve insecticide formulation.