It is common for individuals to feel nauseous both during and after stressful events. This is because there are many connections between the gut and the central nervous system. The endocannabinoid system is a network of neurotransmitters that regulates the sensitivity and feelings within the stomach, intestines, and abdomen. This system significantly influences the management and control of nausea. One way it does this is by regulating ghrelin, a hormone that stimulates hunger and regulates mood.
Ghrelin increases during times of stress. Researchers believe that this may be a way of coping with stress by regulating anxiety. As ghrelin influences appetite and the stomach, nausea can sometimes occur as a side effect. Stressful events can also cause a type of recurring sickness that returns, even when the event is no longer happening. This condition, known as anticipatory nausea, may occur when an individual remembers or thinks about an event that had previously caused nausea or vomiting.