The objective of this study was to analyze cases of dogs diagnosed with strychnine poisoning at the Center for Research and Advanced Studies in Animal Health (CIESA), Mexico. This is a retrospective study based on information from cases that occurred between 2018 and 2021, in which clinical records from the toxicology department were analyzed and systematized. It should be noted that strychnine was identified in the laboratory using a qualitative test. A descriptive method was applied for reporting results, considering variables of epizootiological interest (geographical area of occurrence, type of sample, age, and breed of the affected animals). A total of 17 cases were received from the State of Mexico: Almoloya de Juárez (n = 3), Ixtlahuaca (n = 2), San Mateo Atenco (n = 1), Temoaya (n = 3), Toluca (n = 5), and Valle de Bravo (n = 1), and from the State of Querétaro (n = 2). In 2018...