Consumer Health: What are olfactory hallucinations?

Hallucinations are sensory perceptions of things that are not present. These perceptions may be sights, sounds, smells or sensations on the skin. Causes of hallucinations include head injury, Parkinson's disease, Lewy body dementia, a brain tumor, schizoaffective disorder, temporal lobe seizure and a medication side effect.

With phantosmia, or olfactory hallucinations, a person detects smells that aren't really present. Learn more about olfactory hallucinations from Dr. Jerry Swanson, a Mayo Clinic neurologist.