Olfaction: the neglected sense.

Although olfactory complaints prompt an estimated 200,000 people each year to seek medical consultation in the U.S., there is a dearth of information available in the nursing literature. Recent research links olfaction to degenerative processes in Alzheimer's disease, Parkinson's disease and human immunodeficiency virus infection. This article reviews anatomy and physiology of the olfactory system, describes alterations in smell function and reviews assessment with the University of Pennsylvania Smell Identification Test and odor detection threshold testing. Nurses can advocate thorough assessment and prompt treatment of associated conditions, and educate the patient and family regarding ways to maximize current functioning when olfaction is impaired.