Relevance. In light of the popularization of the use of caffeine-containing products, the question of the combined use of caffeine with substances exhibiting a toxic effect remains open. The doses of caffeine, which have a pronounced antidepressant effect, are also insufficiently studied. The aim of the study was to study the effect of repeated administration of caffeine and dioxidine on the behavioral responses of mice in the Porsolt test. Materials and methods. The experiment was carried out on 36 outbred male mice, divided into 6 groups. Experimental groups for 15 days of the study received caffeine at a dose of 40 mg/kg (first) or 100 mg/kg (second), dioxidine at a dose of 200 mg/kg (third), together with caffeine 40 mg/kg or 100 mg/kg, and dioxidine (fourth and fifth groups, respectively). The animals of the control group were injected with saline. To study the behavior, the Porsolt test was carried out, evaluating the following indicators on the 1st, 8th and 15th days of the experiment: the total time of immobilization, active swimming, climb, the number of grooming and shaking off acts. Results . The administration of caffeine at a dose of 40 mg/kg caused an increase in the time of active swimming and a decrease in the duration of immobilization on the 8th and 15th days. When caffeine was used at a dose of 100 mg/kg, an increase in the time of active swimming was noted with a single exposure, with an experiment duration of 8-15 days, an increase in the duration of immobilization was observed. Dioxidine caused a significant decrease in the time of active swimming and an increase in the duration of immobilization during all days of the experiment. The combined use of caffeine (40 mg/kg and 100 mg/kg) and dioxidine on the 1st day led to a decrease in immobilization and the time of active swimming. In both groups, 100 % animal mortality was observed by the 15th day. Conclusion. The results of the study indicate the presence of an antidepressant effect in caffeine at a dose of 40 mg/kg on the 8th and 15th days of the experiment and the absence of this effect in caffeine at a dose of 100 mg/kg with a duration of administration of 8-15 days. The use of dioxidine led to the absence of antidepressant activity and the presence of the opposite effect. The combined administration of caffeine (40 mg/kg and 100 mg/kg) and dioxidine led to 100 % mortality in the experimental groups by the 15th day of the experiment

Relevance. The consumption of caffeine-containing food in the modern world must necessarily be safe for humans, including should not affect the hereditary material of the body. Objective: to determine the possible effect of caffeine at the cytogenetic level by the micronucleus method on erythrocytes. Materials and Methods. The objects for the study were non-linear mice, which were divided into 6 groups - one control group and 5 experimental groups. The first experimental group and the second in the experiment received caffeine in doses of 40 mg/kg and 100 mg/kg.The control group received saline. Caffeine was administered orally. The mutagen (dioxidine) was injected intraperitoneally. On the 5th day of the experimental study, we performed blood sampling for cytogenetic analysis. Results and Discussion. Our study of the caffeine preparation made it possible to determine the following patterns. Firstly, when administered within 5 days, caffeine at a dose of 40 and 100 mg/kg did not cause an increase in the number of micronuclei in erythrocytes in mice. Secondly, the combined use of caffeine (both at a dose of 40mg/kgand at a dose of 100 mg / kg) and dioxidine significantly increased the level of micronuclei in comparison with the control group. Thirdly, caffeine at a dose of 40mg/kgdid not increase the mutagenic activity of dioxidine, but a dose of caffeine of 100mg/kgwhen combined with a mutagen led to a significant increase in the level of cytogenetic damage. Conclusion. According to our data, caffeine in the experimental study was not a mutagen, but at a dose of 100 mg/kg it represented a comutagenic effect.