Effects of a fixed herbal drug combination (Ze 185) to an experimental acute stress setting in healthy men - an explorative randomized placebo-controlled double blind study

Aims: Considering the negative effects of stress on health and well-being, there is a growing interest to modulate the reactivity of stress response systems. The present study assesses the effects of Ze 185 on psychobiological stress responses in an acute experimental psychosocial stress paradigm. Materials and methods: 72 healthy male participants were randomized to Ze 185 (fixed combination of 4 herbal extracts), placebo or no treatment. 4 days post-baseline, all participants underwent a standardized psychosocial stress paradigm (Trier Social Stress Test) [1]. Participants took either tablets of Ze 185 or placebo or received no treatment during 4 days prior to and the day of the stress exposure. Psychobiological stress responses were repeatedly assessed with the salivary cortisol, heart rate, heart rate variability and self-reported anxiety responses. Key findings: The standardized psychosocial stress paradigm had a significantly impact on all three psychobiological parameters in conditions. Groups did not differ significantly in their salivary cortisol, heart rate and heart rate variability responses over time, but participants in the Ze 185 group showed a significantly decreased stress-induced elevation of subjective anxiety response in comparison to placebo (p = 0.04) and a faster return to baseline. Conclusion: The results show that Ze 185 significantly attenuates the subjective emotional stress response during an acute stress situation, without affecting biological stress response systems. Given that a circumscribed biological stress response is to be considered as an adaptive mechanism, the attenuation of the subjective anxiety response may reflect the possibility of Ze 185 being an effective intervention to reduce subjective stress without affecting adaptive biological stress responses. Since there is no effect on the biological stress response system, it may be assumed that patient's remain responsiveness remains unaltered during treatment with Ze 185