N, N-Dimethyltryptamine (DMT) is a substance used in indigenous rituals. This psychedelic drug has attracted recent interest for its potential in psychotherapy, yet its effects on the brain remain unclear. The main objective of this project is to analyze through various biomarkers, how the brain functions in altered states of consciousness, such as those induced by psychedelic drugs, in a database of a cross-sectional study of patients. The experiment is a placebo-controlled clinical investigation involving 13 healthy participants (7 males and 6 females, 34.4 years ± 9.1 SD). First, the cerebral connectivity between different intra and interhemispheric brain regions was examined, focusing at different time points after administration and between placebo and DMT sessions among participants. Weighted Symbolic Mutual Information (wSMI) was applied, which incorporates weights between EEG channels to improve the precision of brain coordination analysis by assigning relative importance to neural connections between channels. The results of this study revealed significant decrease in overall connectivity during the DMT session, primarily reflected in right frontal connectivity during the DMT session, primarily reflected in right frontoparietal connectivity and the posterior brain region. These areas are associated with sensory perception, which is notably reduced under the influence of substances like DMT, leading to alterations in consciousness and visual perception. Furthermore, graph theory has been applied to calculate connectivity measures such as the Clustering Coefficient (CC) and the Characteristic Path Length (CPL), observing an increase in the Characteristic Path Length. Upon taking DMT, efficiency decreases (increase in CPL), especially in the right posterior area, along with a decrease in the CC indicating a reduction in local segregation and a more random state of the brain network. Finally, different complexity measures commonly used in meditation and consciousness studies were evaluated. Some of these markers assess signal predictability (Higuchi Fractal Dimension – HFD and Waveform Complexity – Cw), while others measure signal regularity (Lempel Ziv Welch – LZW) and Permutation Entropy – PE). The results showed a general increase in brain complexity after DMT administration across all metrics. This brings to light the importance of using techniques that consider both regularity and predictability for a comprehensive complexity comparison, with PE and HFD showing the most promising results. All analyses yielded statistically significant results using repeated measures ANOVA (rmANOVA) within sessions. Additionally, non-parametric methods were used to identify electrodes and regions that show differences after DMT administration.