The common cold is a frequent cause for a partial, temporary loss of smell. Chronic sinus infection also may result in a loss of smell. Other obstructions in the nasal passages, such as polyps, also may cause at least a partial loss of smell. Normal aging is often the cause of a progressive, complete, and permanent loss of smell.

Problems with the inner lining of your nose

Anosmia can be caused by temporary or permanent irritation, or destruction of the mucous membranes lining the inside of your nose. This can be caused by:

  1. Acute sinusitis (sinus infection)
  2. Common cold
  3. Hay fever (allergic rhinitis)
  4. Influenza (flu)
  5. Nonallergic rhinitis (chronic congestion or sneezing not related to allergies)

These conditions are generally the most common causes of loss of smell.

Obstructions of your nasal passages

Anosmia can be caused by something physically blocking the flow of air through your nose. These obstructions can include:

  1. Bony deformity inside your nose
  2. Nasal polyps
  3. Tumors

Damage to your brain or nerves

Your olfactory system, which provides your sense of smell, consists of receptors in the mucous lining of your nose that send information through nerves into your brain. You can lose your sense of smell if any part of the olfactory pathway is damaged or destroyed. This can happen as a result of:

  1. Aging
  2. Alzheimer's disease
  3. Brain aneurysm
  4. Brain surgery
  5. Brain tumor
  6. Chemical exposures to certain insecticides or solvents
  7. Diabetes
  8. Huntington's disease
  9. Kallmann's syndrome (inability of testicles to produce sperm)
  10. Klinefelter syndrome (a condition in which males have an extra X chromosome in most of their cells)
  11. Korsakoff's psychosis (a brain disorder caused by the lack of thiamin)
  12. Malnutrition
  13. Medications (for example, some high blood pressure medications)
  14. Multiple sclerosis
  15. Multiple system atrophy (MSA) (a progressive disorder of the nervous system)
  16. Paget's disease of bone (a disease that affects your bones, sometimes facial ones)
  17. Parkinson's disease
  18. Pick's disease (a form of dementia)
  19. Radiation therapy
  20. Rhinoplasty
  21. Schizophrenia
  22. Sjogren's syndrome (an inflammatory disease that generally causes dry mouth and eyes)
  23. Traumatic brain injury
  24. Zinc deficiency

Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.

Apr. 10, 2014