Repeatedly smelling super glue when there’s no glue around is a type of olfactory hallucination called phantosmia, and it affects roughly 6% of U.S. adults. The most common triggers are ordinary and treatable: sinus infections, lingering effects of a cold, allergies, or nasal polyps. Less often, the smell points to something neurological. Either way, it’s worth understanding what could be behind it, because the causes range from a stuffy nose to conditions that benefit from early detection.
Phantom Smells vs. Real Chemical Sources
Before assuming the smell is coming from inside your head, rule out an actual source. Super glue’s active ingredient releases a sharp, acrid vapor, and dozens of household products give off something similar. Paints, varnishes, adhesives, permanent markers, nail polish, and even new furniture or flooring release volatile organic compounds (VOCs) that can smell strikingly like cyanoacrylate glue. These chemicals off-gas while products are in use and, to a lesser degree, while they’re stored. A recently assembled piece of furniture, a craft project drying in a closed room, or a tube of adhesive with a loose cap can all fill a space with that unmistakable sharp-chemical scent.
If you only notice the smell in one room, near certain objects, or after opening a cabinet, the source is likely environmental. Open windows, move the product, and see if the smell fades. If the smell follows you everywhere, shows up at random, or persists when you’re outdoors and away from any possible source, that’s a strong clue it’s phantosmia.
The Most Common Medical Causes
Phantosmia often shows up during or after something that inflames the nasal passages. Colds, sinus infections, upper respiratory infections, and seasonal allergies can all temporarily scramble the smell-processing cells inside your nose, causing you to perceive odors that aren’t there. Nasal polyps, which are noncancerous growths in the sinus lining, do the same thing by physically disrupting airflow and irritating olfactory tissue. In these cases, the phantom smell usually resolves once the underlying congestion or infection clears.
COVID-19 deserves its own mention. Many people develop phantosmia weeks or even months after a COVID infection, sometimes long after other symptoms have disappeared. The virus can damage olfactory nerve cells, and as those cells regenerate, they occasionally “miswire,” sending distorted signals to the brain. Chemical and burnt smells are among the most frequently reported types. For most people this improves gradually over several months, though recovery timelines vary widely.
Dental problems are an overlooked trigger. Gum disease, dry mouth, and oral infections can produce chemical-tasting or chemical-smelling compounds that you perceive as coming through your nose. If you’ve noticed the smell worsening around meals or alongside a bad taste, it’s worth mentioning to a dentist.
Medications That Distort Smell
Several common drug classes can alter how you perceive odors. Nasal corticosteroid sprays (the kind used for allergies) and oral antibiotics, particularly macrolides and fluoroquinolones, are among the most frequently reported culprits. Antidepressants in the SNRI and SSRI families have also been linked to smell distortion, with duloxetine, paroxetine, and venlafaxine showing the strongest associations in a large World Health Organization safety database analysis. Nicotine replacement therapies (patches, gum, varenicline) and a class of diabetes drugs called incretin mimetics round out the list.
If you started or changed a medication shortly before the smell appeared, that timing is worth noting and discussing with whoever prescribed it. Medication-related smell changes typically reverse after the drug is stopped or adjusted.
Neurological Explanations
The brain’s smell-processing centers sit in the temporal lobe, nestled among structures involved in memory and emotion. When something disrupts these areas, phantom smells can result. Migraines are one of the more common neurological triggers. Some people experience an “olfactory aura,” a sudden strange smell that arrives before the headache itself. Chemical, smoky, and burnt odors are classic descriptions.
Temporal lobe epilepsy is a less common but important cause. About 5% of people with focal epilepsy report olfactory auras, and the vast majority of those cases originate in the temporal lobe. The phantom smell in this scenario is usually brief (seconds to a couple of minutes), comes on suddenly, and may be accompanied by a wave of déjà vu, a rising sensation in the stomach, or a brief moment of confusion. These episodes can be subtle enough that people don’t recognize them as seizure activity.
Traumatic brain injuries, even mild ones that happened years ago, can also cause phantosmia by damaging the olfactory bulb or the nerve pathways running between the nose and brain.
Metabolic and Systemic Conditions
Your body’s internal chemistry can change what you smell. Hypothyroidism has been associated with phantom odors, likely because thyroid hormones influence how olfactory neurons function. Kidney disease is another possibility: when the kidneys can’t adequately filter waste, ammonia and urea build up in saliva and breath, producing a sharp chemical odor that can resemble solvents or adhesives. Liver dysfunction creates a similar effect through different waste products. Deficiencies in zinc, vitamin B12, or iron have also been linked to smell disturbances, since these nutrients are essential for healthy olfactory nerve turnover.
How Doctors Figure Out the Cause
The diagnostic process usually starts simply. A doctor will ask when the smell began, how often it happens, whether it’s in one nostril or both, and what else was going on in your health around that time. Nasal endoscopy, where a thin camera is passed through the nose, lets them look directly at the nasal lining and olfactory cleft for signs of inflammation, polyps, crusting, or unusual growths.
If the nasal exam is normal and the history suggests something beyond a sinus issue, the investigation broadens. Blood work can screen for thyroid problems, kidney function, liver health, zinc levels, vitamin B12, and other metabolic markers. A CT scan may be ordered to get a detailed look at the sinuses, particularly if chronic sinusitis or structural problems are suspected. MRI is the tool of choice when the concern is neurological: it can evaluate the olfactory bulb size (which shrinks in certain conditions), check for brain tumors, assess old traumatic injuries, and look for early signs of neurodegenerative disease.
When Phantom Smells Signal Something Serious
Most phantosmia traces back to something benign, but certain accompanying symptoms suggest a more urgent cause. A phantom smell paired with sudden confusion, difficulty speaking, weakness on one side of the body, or a severe headache could indicate a stroke. Repeated brief episodes of a strange smell combined with staring spells, involuntary movements, or memory gaps raise the possibility of seizures. A phantom smell that steadily worsens over weeks, especially alongside new headaches, vision changes, or personality shifts, warrants prompt evaluation to rule out a brain tumor.
Phantosmia appearing alongside tremors, a shuffling walk, or changes in handwriting can be an early sign of Parkinson’s disease, sometimes showing up years before the more recognizable motor symptoms. Similarly, progressive smell distortion combined with increasing forgetfulness may point toward Alzheimer’s disease. In both cases, early detection opens the door to treatments that can slow progression.