Phantosmia (Phantom Smell)

What is Phantosmia?

Phantosmia is experiencing non-existent or imaginary odors, in other words, a person begins to hallucinate about smells that are not present. The smells may be felt in either one or both nostrils; as they are invariably malodorous or foul-smelling; and may be present the entire time or felt occasionally. Most often, the individuals experience a smoky smell. Phantosmia is not a worrying condition because the problem may resolve itself within weeks or months and rarely, it might take years to resolve.

There is a prevalence of 0.8-25 percent of phantosmia in the general population, accounting for 10-20 percent of olfactory disorders (related to smell). Changes in the olfactory neural networks make phantosmia sensorineural in nature. In most cases, women appear to be more affected by these smell hallucinations.

There are 2 types of phantosmia. They are:

• Central - involves the regions within the brain that process smell signals.
• Peripheral - involves the olfactory neurons (nerve cells) that transmit the smell signal to the brain.