• Home

Home > Medical Reference > Encyclopedia (English)

Toggle: English / Spanish

Smell - impaired

• Overview
• Treatment

Definition:

Impaired smell is the partial or total loss of the sense of smell.

Alternative Names:

Loss of smell; Anosmia

Considerations:

The loss of smell is usually an insignificant result of nasal congestion or obstruction, but it can sometimes indicate a neurological disorder. Loss of the sense of smell may be idiopathic (without any identifiable cause).

Some loss of smell occurs normally with aging. In most cases, there is no obvious or immediate cause, and there is no treatment.

Temporary loss of the sense of smell is common with colds and nasal allergies , such as hay fever ( allergic rhinitis ). It may occur following a viral illness.

The sense of smell is often lost with disorders that prevent air from reaching the part of the nose where smell receptors are located (the cribriform plate, located high in the nose). These disorders may include nasal polyps , nasal septal deformities, and nasal tumors.

Other disorders that may cause a loss of the sense of smell include tumors of the head or brain, head trauma, and a wide variety of endocrine, nutritional, Alzheimer's dementia, and nervous disorders.

Many medications may change or decrease the ability to detect odors.

Most people who lose the sense of smell can still differentiate salty, sweet, sour, and bitter tastes, which are sensed on the tongue. They may not be able to distinguish other flavors. Some spices (such as pepper) may stimulate facial nerves and may be felt rather than smelled.

Common Causes:

• Natural aging process
• Recent viral upper respiratory infection
• Nasal decongestants
• Lead poisoning
• Drugs (such as amphetamines, estrogen, naphazoline, phenothiazines, prolonged use of nasal decongestants, reserpine)
• Radiation therapy
• Nasal or sinus surgery
• Tracheostomy
• Nasal or brain tumors

• Review Date: 4/28/2006
• Reviewed By: Alden J. Pearl M.D., Clinical Assistant Professor, Department of Otolaryngology, State University of New York Health Science Center at Brooklyn, Brooklyn, NY. Review provided by VeriMed Healthcare Network.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process . A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.