Acute, accidental, oral poisoning with carbofuran in a chronic alcoholic was presented. In clinical picture muscarinic and nicotinic symptoms dominated. Toxicological examination revealed non acetylcholinesterase activity. A role of an interview and physical symptoms in diagnosing the poisoning with cholinesterase inhibitors, a specific treatment conduct and its side effects were discussed. So far six cases of poisoning with cholinesterase inhibitors have been treated at II Department of Internal Diseases and Acute Poisoning in Tarnów. The case presented below was characteristic for a considerable intensification of side effects during the treatment conduct. It was the reason for presenting this case.