Reports of food poisoning caused by pesticide-contaminated food are rare in the medical literature. In this paper, we report six patients who suffered food poisoning in two separate episodes in which the pesticide coumaphos was apparently misused as a food flavoring. These six patients presented not only the general manifestations of gastroenteritis, but also some unusual extraintestinal symptoms. These included cholinergic overactivity (miosis, urinary incontinence and hypersalivation) that led us to suspect organophosphate intoxication. This diagnosis was confirmed by serial changes in RBC cholinesterase and pseudocholinesterase activity, and by the presence of coumaphos in the contaminated food. Of the six patients, one was dead on arrival. Another patient developed progressive respiratory failure and required mechanical ventilation. The mortality rate among our cases was 16.7%. Since the coumaphos was apparently added to food during cooking, its toxic effects do not appear to be mitigated by heating. When food poisoning cases present with both gastroenteritis and unusual autonomic symptoms, the autonomic syndromes will aid in the diagnosis and management of these critically ill patients.