What are the causes of phantosmia?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: June 16, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Phantosmia is primarily caused by temporal lobe dysfunction, degenerative or psychiatric disease, as well as other factors such as upper respiratory infections, sinus infections, nasal polyps, and head trauma. The perception of odors that aren't actually present can be triggered by various conditions, including neurological disorders like migraines, epilepsy, Parkinson's disease, and Alzheimer's disease 1. Certain medications, particularly some antidepressants, stimulants, and antipsychotics, may also induce phantosmia as a side effect.

Some key factors to consider in the diagnosis of phantosmia include:

  • Upper respiratory infections
  • Sinus infections
  • Nasal polyps
  • Head trauma
  • Neurological conditions like migraines, epilepsy, Parkinson's disease, and Alzheimer's disease
  • Certain medications, such as antidepressants, stimulants, and antipsychotics
  • Exposure to toxic chemicals
  • Dental problems
  • Hormonal changes during pregnancy or menopause

According to the most recent study 1, the causative factors for olfactory impairment can be categorized into three main groups, including conduction loss from sinonasal passage obstruction, sensorineural loss from olfactory neuroepithelial damage, and dysfunction from central nervous system disorders. It is essential to consult a healthcare provider if you experience persistent phantosmia, as treatment depends on identifying the underlying cause. Options may include saline rinses for nasal issues, medication adjustments, or in rare cases, surgical interventions for structural problems. The mechanism involves abnormal activation of the olfactory system, either through direct irritation of olfactory neurons or disruption of brain regions that process smell 1.

From the Research

Causes of Phantosmia

The causes of phantosmia, a condition characterized by the perception of smells in the absence of olfactory stimuli, can vary. Some of the possible causes include:

  • Infections 2
  • Traumatic brain injury 2, 3
  • Psychiatric disorders, such as schizophrenia 2
  • Neurological disorders, including Parkinson's disease 4
  • Other factors, such as changes in brain structure following an infection 2

Associated Conditions

Phantosmia can be associated with various conditions, including:

  • Parosmia, a distorted olfactory sensation in the presence of an odor 2, 3
  • Qualitative olfactory dysfunctions, which can be secondary to neurological diseases 3
  • Hyposmia, a reduced ability to smell 4, 5

Triggers and Exacerbating Factors

Certain factors can trigger or exacerbate phantosmia, including:

  • Ambient humidity, barometric pressure, and season 5
  • Intranasal pressure, such as coughing 5
  • Eating or sniffing, which can replace the phantosmia with actual flavors 5
  • Weather changes, such as thunderstorms 5

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Parosmia and Phantosmia: Managing Quality Disorders.

Current otorhinolaryngology reports, 2023

Research

Phantosmias and Parkinson disease.

Archives of neurology, 2008

Research

Phantosmia as a meteorological forecaster.

International journal of biometeorology, 2013

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.