Smelling cinnamon, smoke, perfume, or any other odor when no physical source exists is a phenomenon called phantosmia, and it is far more common than most people realize. Population-based research puts the prevalence of phantom smells at roughly five percent of older adults, with women affected more than men. The causes range from completely benign to medically significant, and the specific scent you perceive, whether it is warm and spicy or acrid and burnt, does not by itself tell you which category you fall into.
What Phantosmia Actually Is
Doctors classify smell disorders into a few categories. Reduced or absent smell is called hyposmia or anosmia. Distorted perception of a real odor, like coffee suddenly smelling rancid, is called parosmia. Phantosmia is different from both: it is the perception of an odor when no chemical stimulus is present at all. In clinical terms, it is an olfactory hallucination.1Chemical Senses. Distortion of Olfactory Perception: Diagnosis and Treatment The word “hallucination” sounds alarming, but phantosmia usually does not share the clinical weight that term carries in psychiatry. Most episodes are brief, self-limiting, and have a straightforward explanation.
The phantom smell can originate at more than one level of the nervous system. It may start in the olfactory neurons inside your nose, in the nerve fibers that carry smell signals to the brain, or in the brain itself. Research on the condition suggests that when olfactory sensory neurons are dying or regenerating, the resulting miscommunication can generate a false signal that your brain interprets as a specific scent.2PubMed Central. Phantom smells: a prevalent COVID-19 symptom that progressively sets in One large survey found that phantom odor perception was inversely associated with age, especially among women, which fits with the idea that age-related loss of olfactory neurons reduces the raw material for these misfiring signals.3JAMA Otolaryngology–Head & Neck Surgery. Factors Associated With Phantom Odor Perception Among US Adults
What Phantom Smells Usually Smell Like
If you search online, you will find plenty of people reporting phantom cinnamon, but that is not the most commonly described phantom scent. In a population-based study of older adults who reported phantom smells, the single most frequent description was smoky or burnt, reported by about half of those who could specify the smell. Other descriptions included rotten, moldy, metallic, cooked food, perfume, and flowery scents.4PubMed Central. Phantom Smells: Prevalence and Correlates in a Population-Based Sample of Older Adults Cinnamon, coffee, baking bread, and other pleasant or spicy smells do appear in clinical reports, but they are less commonly studied because people who smell something pleasant are less likely to seek medical attention than people who smell smoke or decay.
This matters because many online discussions imply that specific scents map to specific causes. They rarely do. The character of a phantom smell, whether cinnamon-sweet or garbage-foul, tells you very little about what is driving it. A person recovering from COVID might smell cinnamon; a person with a migraine might smell cinnamon; a person with no diagnosable issue at all might also smell cinnamon. It is the surrounding circumstances, timing, and accompanying symptoms that point toward the cause, not the scent itself.
Post-Viral Causes, Especially COVID-19
Upper respiratory infections have long been one of the leading causes of smell disorders, and COVID-19 dramatically increased public awareness of this. The SARS-CoV-2 virus damages olfactory neurons in the nasal lining, and while most people recover their smell within weeks, a subset develops longer-lasting problems including phantosmia. A follow-up study of people recovering from COVID-related smell loss found that phantosmia was reported by about a quarter of participants at a later follow-up, up from roughly ten percent during the acute illness.5PubMed Central. A follow-up on quantitative and qualitative olfactory dysfunction and other symptoms in patients recovering from COVID-19 smell loss In other words, phantom smells often emerged not during the infection but during recovery, likely as damaged neurons attempted to regenerate.
Among people classified as “smell long-haulers,” those still experiencing smell dysfunction well after their infection, about a third reported phantosmia, compared to roughly thirteen percent of those whose smell had recovered.5PubMed Central. A follow-up on quantitative and qualitative olfactory dysfunction and other symptoms in patients recovering from COVID-19 smell loss The good news is that post-viral phantosmia tends to fade as the olfactory system finishes its repair. The bad news is that “finishes its repair” can take months, and the phantom smells can be distressing in the meantime. This pattern, phantom odors emerging during the recovery window rather than the acute damage, is consistent with the broader understanding that olfactory distortions are linked to periods of neuron death or regrowth.2PubMed Central. Phantom smells: a prevalent COVID-19 symptom that progressively sets in
COVID is the most talked-about viral cause right now, but the same pattern applies to the common cold, influenza, and other respiratory infections that can temporarily damage your sense of smell. If your phantom cinnamon smell started within a few months of a bad cold or respiratory illness, this is a strong candidate explanation.
Medications and Polypharmacy
A cause that surprises many people is medication. A study using data from a large national health survey found that taking five or more prescription medications was associated with about seventy percent greater odds of reporting phantom smells. Among adults sixty and older, certain drug classes stood out: diabetes medications, cholesterol-lowering drugs, and proton pump inhibitors (commonly prescribed for acid reflux) were each associated with roughly seventy-five to ninety percent higher odds of phantom odor perception.6PubMed Central. Prescription Medication Use and Phantom Odor Perception Among US Adults
This does not mean those medications cause phantosmia directly in every case; it could reflect the underlying conditions being treated, or interactions between drugs. But it does mean that if you started smelling phantom cinnamon around the same time as a medication change, it is worth mentioning to your doctor. Adjusting or switching medications sometimes resolves the problem.
Migraine Aura
Some people who get migraines experience an aura phase before the headache hits, and while visual disturbances like flashing lights or zigzag lines get the most attention, olfactory auras happen too. A person might smell burning, smoke, or other odors for thirty minutes or so before the headache arrives.7PubMed Central. Various presentations of the olfactory hallucination in two patients with migraine disease: Case report The smell can precede visual symptoms and the pain itself, which means some people do not initially connect the two.
If you notice phantom scents reliably appearing in the hour or two before a headache, or alongside light sensitivity and nausea, an olfactory migraine aura is a real possibility. Tracking whether the phantom smell consistently precedes a headache is the simplest way to investigate this on your own. Some people who get migraines with olfactory aura find the smell changes over time, shifting between burnt, chemical, or sweet categories across different episodes. The pattern of timing matters more than the specific scent.
When Phantom Smells Signal Something More Serious
Two categories of phantom smells warrant more urgent attention: those connected to seizures and those connected to neurodegenerative disease.
In temporal lobe epilepsy, phantom smells can be the aura that precedes a seizure. A study of patients with olfactory seizure auras found that the smells were of various types and unpleasant in only a minority of cases. In those patients, the seizure focus was localized to the mesial temporal region, and the majority had a tumor involving the amygdala, the brain structure closely tied to emotion and smell processing.8PubMed. Olfactory epileptic auras Seizure-related phantom smells are typically brief (seconds to a couple of minutes), may be followed by a period of confusion or altered awareness, and tend to recur in a stereotyped pattern. If your phantom smell is always the same, lasts under a minute, and you feel “off” or disoriented afterward, that is a pattern worth describing to a neurologist.
Phantosmia has also been proposed as an early, pre-motor manifestation of Parkinson’s disease. While Parkinson’s is well known for causing reduced smell, researchers have suggested that qualitative distortions, including phantom odors, deserve closer attention in the prodromal phase of the disease, the period before characteristic movement symptoms appear.9JAMA Neurology. Phantosmias and Parkinson Disease This does not mean that smelling cinnamon makes Parkinson’s likely. It means that persistent phantom smells occurring alongside other changes, such as a reduced sense of smell, sleep disturbances, or subtle motor changes, might warrant further evaluation.
Head injuries are another pathway. Even mild traumatic brain injuries can damage the delicate olfactory nerve fibers that pass through the thin bone at the base of the skull. Advanced neuroimaging of service members with suspected olfactory problems after head trauma revealed evidence of frontal lobe injury in all cases examined, sometimes subtle and subcentimeter in size.10Oxford Academic. Olfactory Testing Informs the Decision Process to Obtain Advanced Neuroimaging in Traumatic Brain Injury If your phantom smells began after a fall, car accident, or blow to the head, mention the history to your doctor even if it happened months ago.
Anxiety, Stress, and Psychiatric Connections
Olfactory hallucinations have been associated with various psychiatric conditions, most famously with psychotic disorders like schizophrenia. But they have also been reported as a symptom of anxiety, sometimes appearing as the first and only presenting symptom. A case report described olfactory hallucinations arising in a patient with anxiety disorder who had no other psychotic features.11PubMed Central. First-episode olfactory hallucination in a patient with anxiety disorder: A case report The mechanism is not entirely clear, but heightened arousal and hypervigilance, both common in anxiety states, may lower the threshold at which the brain interprets ambiguous neural signals as real smells.
Stress can also amplify the brain’s tendency to fill in sensory gaps. Periods of poor sleep, high emotional stress, or major life transitions can bring on transient phantom smells in otherwise healthy people. These episodes usually resolve as the stressor fades, and they do not necessarily mean anything is wrong with your nose or brain.
Your Brain Filling In the Blanks
One of the more fascinating aspects of phantosmia is how much of it seems to be the brain’s own construction. Functional MRI studies have shown that when patients recall their phantom smells, the activation in smell-related brain regions is actually greater than activation produced by remembering a real odor or even smelling one in real time.12Journal of Computer Assisted Tomography. Taste and Smell Phantoms Revealed by Brain Functional MRI (fMRI) The brain is not just passively receiving a wrong signal; it is actively constructing the experience.
This fits with a broader model of how the brain works: it constantly generates predictions about the sensory world and then checks those predictions against incoming data. When incoming data is degraded or absent, as when olfactory neurons are damaged or when sensory input is reduced, the brain’s own predictions can dominate, producing a phantom percept.13PubMed. The Bayesian brain: phantom percepts resolve sensory uncertainty This is the same basic principle behind visual hallucinations in people losing their sight (Charles Bonnet syndrome) and the phantom limb sensations experienced after amputation. Your brain expects input and, in its absence, generates its own.
Expectation plays a real, measurable role. A controlled experiment found that when people were told a virtual reality environment included modeled scents, they reported experiencing diverse olfactory sensations, describing specific smells connected to the virtual setting, even though no scent was actually delivered.14Scientific Reports. Believing in simulated virtual scents produces reported olfactory sensations This is not people being gullible; it is the brain’s smell system responding to top-down cues. In everyday life, the same principle means that strong visual cues (seeing a cinnamon candle), strong memories, or even conversation about a smell can nudge your brain toward producing a phantom version of it.
Memory, Nostalgia, and Personal Meaning
Phantom smells are not always random neural noise. In the same population study that catalogued common phantom smell types, a small but intriguing subset of individuals reported phantom smells with an autobiographical connotation, smells tied to specific personal memories or meaningful events. The researchers noted that this suggests phantom smells can be linked to the brain’s memory systems, not just to misfiring peripheral neurons.4PubMed Central. Phantom Smells: Prevalence and Correlates in a Population-Based Sample of Older Adults
Smell is uniquely tied to memory compared to other senses. The olfactory system has unusually direct connections to the hippocampus and amygdala, brain regions central to memory formation and emotion. This wiring means that odor-triggered memories tend to be more vivid and emotional than memories triggered by sight or sound. It also means that a phantom smell of cinnamon could be your brain replaying a meaningful memory fragment, Thanksgiving baking, a grandparent’s kitchen, a childhood home, in olfactory form. This does not make it any less “real” as a sensory experience, but it does shift the likely explanation away from disease and toward the brain’s normal memory-emotion apparatus doing its thing unbidden.
Sinus and Dental Issues
Before assuming neurological causes, it is worth ruling out local problems in the nose and sinuses. Chronic sinusitis, nasal polyps, and dental infections can all produce unusual smells that feel like they are coming from nowhere because you have adapted to their constant presence. Sinus infections can generate foul or oddly sweet odors, and because the source is inside your own body, there is no external source to find. Cases of sinusitis caused by dental problems, such as retained material in the maxillary sinus, have presented with localized pain and unusual smell or taste sensations.15Nigerian Journal of Clinical Practice. Maxillary Sinusitis Caused by Retained Dental Impression Material
If you have a persistently odd smell that others cannot perceive, especially one that is hard to describe precisely and accompanied by facial pressure, postnasal drip, or a bad taste, the source might be a chronic low-grade sinus or dental issue rather than phantosmia in the neurological sense. An ENT examination or dental evaluation can usually distinguish between the two.
How Doctors Figure Out the Cause
If phantom smells persist or are accompanied by other neurological symptoms, a clinical evaluation typically begins with a detailed history: when the phantom smells started, how often they occur, how long each episode lasts, whether they are associated with headaches or seizures, what medications you take, and whether you have had recent infections or head injuries. Standardized smell tests exist that can measure overall olfactory function and help distinguish between someone with broadly impaired smell (who may be generating phantoms to compensate for lost input) and someone with normal baseline smell who is getting extra, false signals.16PubMed Central. Clinical assessment of patients with smell and taste disorders
Brain imaging is not routinely needed. It is typically reserved for cases where the history or examination raises concern about a structural cause, such as a brain tumor or lesion. If episodes are brief, stereotyped, and followed by confusion, an EEG may be ordered to evaluate for seizure activity. For most people with occasional phantom smells and no red-flag symptoms, reassurance and monitoring is the standard approach.
Treatment Options
Most cases of phantosmia resolve without treatment, especially when the cause is post-viral or related to medication. When a medication is identified as a likely trigger, adjusting the regimen sometimes eliminates the phantom smell. For post-COVID phantosmia, smell training, repeated deliberate exposure to a set of distinct odors, is the most commonly recommended rehabilitation approach, and it may speed recovery of normal olfactory function while displacing phantom signals.
For severe, persistent phantosmia that resists all other approaches, surgical treatment exists. Endoscopic excision of the olfactory tissue in the nose has been performed on a small number of patients with unremitting phantosmia. In one surgical series, complete resolution occurred in seven of eight patients, and overall olfactory function was potentially preserved.17JAMA Otolaryngology–Head & Neck Surgery. Long-term Follow-up of Surgically Treated Phantosmia Surgery is a last resort, reserved for people whose phantom smells are constant and significantly impair quality of life, but its existence is worth knowing about.
Functional brain imaging studies in phantosmia patients have shown that before treatment, activation patterns in the brain tend to be lateralized to the right hemisphere in the anterior frontal and temporal cortices. After successful treatment, this activation pattern shifts, suggesting that the brain reorganizes once the phantom input is no longer present.18Journal of Computer Assisted Tomography. Lateralization of Brain Activation to Imagination and Smell of Odors Using Functional Magnetic Resonance Imaging (fMRI) The brain adapts both to the phantom and to its removal.
When to Worry and When to Wait
Occasional phantom smells that last seconds to minutes, happen a few times a week or less, and are not accompanied by confusion, headache, or other neurological symptoms are unlikely to represent anything dangerous. They are especially common during cold and flu season, in the months after a respiratory infection, and during periods of high stress or sleep deprivation. If your phantom cinnamon has been appearing intermittently for a few weeks and you recently had a cold, there is a good chance it will fade on its own.
Situations that do justify prompt medical evaluation include phantom smells that are always the same and are followed by confusion or loss of awareness (suggestive of seizure activity); phantom smells accompanied by progressive loss of smell, tremor, or changes in gait (suggestive of neurodegenerative disease); phantom smells that began after head trauma; and phantom smells that are constant, all day every day, with no breaks. The last pattern, while usually benign in terms of what is causing it, can significantly affect appetite, mood, and quality of life and warrants treatment discussion regardless of the underlying cause.
For everyone else, the phantom cinnamon in your kitchen is most likely your brain doing what brains do: predicting, constructing, and occasionally getting creative with the sensory world in the absence of a clear signal to ground it.