Assessment of nausea and vomiting, adults

Nausea and vomiting are extremely common symptoms and may be caused by a vast array of medical conditions. [1] Koch KL. Nausea and vomiting. In: Wolfe MM, Davis GL, Farraye FA, et al, eds. Therapy of digestive disorders, 2nd ed. Philadelphia, PA: Saunders; 2006:1003-1117. [2] Koch KL. Diagnosis and treatment of neuromuscular disorders of the stomach. Curr Gastroenterol Rep. 2003;5:323-330. http://www.ncbi.nlm.nih.gov/pubmed/12864963?tool=bestpractice.com [3] Stern RM, Koch KL, Andrews P. Nausea: mechanisms and management. New York, NY: Oxford University Press; 2011. The presentation can be acute or chronic and ranges from a mildly annoying symptom to a condition that impairs quality of life or is a marker of a life-threatening disease.

There are 2 general mechanisms of nausea and vomiting:

Neurological

• Stimulation of the area postrema, which 'senses' noxious chemical agents (e.g., poisons, chemotherapy agents, digoxin) and subsequently stimulates the vagal nuclei, which evokes nausea and co-ordinates the emesis reflex.

• CNS diseases such as infections or brain tumours stimulate CNS structures and elicit nausea and vomiting, ultimately through vagal pathways.

Peripheral

• Diseases and disorders that originate in peripheral organ systems, such as the GI tract, stimulate vagal or spinal afferent nerves that connect with the vagal sensory (tractus solitarius) and vagal efferent motor nuclei. Ultimately, cortical centres where nausea is perceived and the efferent pathways that mediate vomiting are stimulated.

• Tumours, infections, and drugs in the periphery may cause local dysfunction in a variety of organ systems that is sensed as nausea, and severe nausea eventually evokes vomiting.