Ginsenosides are the major active compounds found in Panax ginseng and are well-known for their adaptogenic properties. Scientific research has shown that ginsenosides may exert modulatory effects on the autonomic nervous system, including the parasympathetic branch. Studies have reported that ginsenosides can influence neurotransmitter release and receptor activity, particularly acetylcholine, which is a key neurotransmitter of the parasympathetic system. Animal studies indicate that certain ginsenosides (such as Rg1 and Rb1) can enhance cholinergic transmission, promote vagal activity, and attenuate stress-induced sympathetic overactivity, thereby supporting parasympathetic tone.

Clinical research in humans is more limited, but some trials suggest that ginseng extracts may help regulate heart rate variability and reduce stress, both of which are partly mediated by the parasympathetic nervous system. However, the evidence is not unequivocal, and more robust, large-scale human trials are needed to confirm these effects. Overall, while traditional use of ginseng focuses broadly on vitality and energy, there is a moderate scientific rationale—largely from preclinical studies—for its potential to support parasympathetic nervous system function.