|MadSci Network: Medicine|
Vomiting is a complex reflex act common not only to people but also to lower animals possessing an alimentary tract and is basically a protective mechanism to eliminate toxic or irritating substances from the body. In humans it can be initiated by emotional, chemical(certain drugs), or physical stimulation. For an in depth discussion see Best & Taylor, The Physiological Basis of Medical Practice, Sixth Edition, pp. 572-75 (or later editions)
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