Objectives: The aim of the research was to analyze the nature of changes and tendencies observed in the frequency, circumstances and causes of acute intentional poisonings within the agglomeration of Łódź, Poland. The study related to adults. Material and Methods: As the research material, medical records of patients hospitalized due to an acute poisoning in the Department of Toxicology in Łódź were used. Information on the hospitalized patients was gathered in the database created in accordance with the assumed criteria and an approved system of the collection of variables describing the issues of intentional acute poisonings. Results: In the analyzed period, within the group of 18 918 adult patients hospitalized due to an acute poisoning, male patients prevailed, accounting for 57.17% of the whole group. Intentional poisonings constituted 40.19% of all poisonings, with women dominating within that group of patients – accounting for approximately 58.63%. The largest group was formed by young people, 18–35 years old, accounting for 43.22%. The average age of the intentionally poisoned patients showed an upward tendency; this tendency concerned women to a larger extent. Medications played the most powerful role in acute intentional poisonings. Within the whole population, they were responsible for 97.27% of intoxications. The analysis of the dynamics of changes in the percentage of patients referred for further mental treatment revealed that the number of patients continuing hospital treatment in psychiatric wards tended to grow. Conclusions: Observations indicating that women are more likely to attempt intentional poisoning, and that the number of patients with psychiatric disturbances tended to grow in the analyzed period, demonstrate an urgent need for preventive measures to be taken in the local communities. Int J Occup Med Environ Health. 2020;33(1):77–90