Your sense of smell allows you to enjoy the aromas of nature and your favorite foods. It can also serve as a warning system, alerting you to spoiled food, a gas leak or smoke from a fire. If you have a smell disorder, it can disrupt your quality of life. It is estimated that one to two percent of North Americans have a smell disorder, most commonly men in their 60s, although anyone can be affected.
How Does Your Sense of Smell Work? 
Before learning about smell disorders, it is important to understand how the sense of smell works.
Your sense of smell, along with taste, is part of your chemosensory system (chemical senses). Within the tissues high in the nose are olfactory sensory neurons. These cells connect directly to the brain, and each one has its own odor receptor. When a substance – like a cup of coffee – releases microscopic molecules, it stimulates these receptors. This information is then passed on to the brain, where the smell is identified.
There are more smells in your environment than there are receptors in your nose, and any given molecule can stimulate a combination of receptors. This creates a unique representation of a scent in your brain that can be recognized as a particular smell.
What Are the Different Smell Disorders?
A smell disorder describes a decrease in ability to smell or changes in the way odors are perceived. Common smell disorders include:
- Hyposmia – reduced ability to detect odors.
- Anosmia – complete inability to detect odors.
- Parosmia – change in normal perception of odors (familiar smells seem distorted).
- Phantosmia – sensation of odors that aren’t there.
What Causes Smell Disorders?
Smell disorders can have a variety of causes, including:
- Aging
- Upper respiratory infections
- Smoking
- Growths in nasal cavities
- Head injury
- Hormonal disturbances
- Dental problems
- Exposure to chemicals
- Certain medications, particularly antibiotics and antihistamines
- Radiation for head and neck cancers
- Diseases that affect the nervous system, like Parkinson’s or Alzheimer’s
Can Smell Disorders Be Treated?
Smell disorders can be treated by otolaryngologists (ear, nose and throat physicians). The first step in seeking treatment is to undergo an assessment, which includes a physical exam, review of health history and a smell test. Treatment depends on the underlying cause, although not all cases can be cured.
For more information or to schedule an appointment, call the experts at PDX ENT today.
