Perceiving a smell that isn’t actually present, like sizzling bacon, can be a disorienting experience. This phenomenon, often temporary, can leave individuals wondering about its origin.
Understanding Phantom Smells
A phantom smell, scientifically known as phantosmia, is an olfactory hallucination where a person perceives an odor without an external stimulus. These perceived smells vary widely; some are pleasant, but many report unpleasant odors like burnt toast, smoke, chemicals, or something rotten. The sensation can occur in one nostril or both and may be intermittent or constant.
Phantosmia arises from disruptions within the olfactory system, the network of nerves and brain regions processing smells. These disruptions can occur in the peripheral olfactory system (nose and associated nerves) or in the central olfactory system (brain’s smell-processing centers). Approximately 10-20% of all smell disorders are classified as phantosmia.
Common Reasons for Phantom Smells
Several common conditions can lead to phantom smells. Issues affecting the sinuses and nasal passages are frequent culprits, including infections like sinusitis, nasal polyps, allergies, or severe common colds. Between 52% and 72% of smell-related disorders are linked to sinus issues. These conditions can inflame or disrupt the olfactory nerves, leading to misperceptions of odor.
Migraines can also trigger olfactory hallucinations, where phantom smells serve as an aura symptom preceding or accompanying the headache. These smells are often unpleasant, such as gasoline or rotting meat, and typically last between 5 and 60 minutes. Dental problems, specifically infections in teeth or gums, may also impact nearby nerves and cause phantom smells, which usually resolve once the infection is treated.
Certain medications can have side effects that alter or create phantom smells. Head injuries, even mild concussions, can sometimes lead to temporary changes in smell perception, including phantosmia, due to damage to olfactory pathways. As people age, phantosmia can occur more frequently in adults over 60 years old.
When to Consult a Doctor
Consult a healthcare professional if phantom smells are persistent or recurring, or if they significantly disrupt daily life or cause distress. While many causes of phantosmia are benign and may resolve on their own, medical evaluation can help rule out more serious underlying conditions.
Medical attention is important if the phantom smell is accompanied by other symptoms such as headaches, seizures, changes in vision, weakness, or numbness. A doctor can perform a thorough examination, which may include a detailed history of your symptoms, a smell test, or imaging studies like an MRI or CT scan of the brain or sinuses to identify the cause. Addressing the root cause is the primary approach to managing phantosmia, and your doctor can guide you on the appropriate steps.