The human organism can be understood as a complex system of dynamic interactions regulating physiological functions to maintain a state of homeostasis. Acute mental stress disrupts homeostasis and triggers a cardiovascular response controlled by the autonomic nervous system. We investigated the effects of acute mental stress on dynamic interactions between 20 vital parameters of haemodynamics, heart rate variability, QT variability, respiration, and skin conductance in 35 healthy subjects. To characterize dynamic interactions, we calculated symbolic transfer entropy between all vital parameters during baseline and acute mental stress. Significant changes were found in the dynamic interactions for 206 of 400 parameter combinations between baseline and acute mental stress (p < 0.05, Bonferoni-Holm corrected). Overall, dynamic interactions increased significantly by 9.3 % (p < 0.001) compared to baseline. Specifically, acute mental stress caused a 22 % increase of interactions between vital parameters that are dominated by sympathetic and parasympathetic nervous system. Our results indicate that acute mental stress leads to increased autonomic regulation. The characterization of dynamic interactions during acute mental stress provides insights for a better understanding of autonomic regulation processes.