It isn’t quite clear why some people are more sensitive to noxious smells than others, but osmophobia— a psychological hypersensitivity to smells—is a common part of the migraine experience.
Generally, chemical fumes such as cleaners and gasoline are those most likely to induce a migraine attack. During a migraine, many odors can be bothersome.
What Is Osmophobia?
During a migraine, you may experience an aversion to smells that you regard as unpleasant. This could be due to a physiological cause, a psychological one, or a combination of the two.
When it is psychological, it is referred to as osmophobia.
You may, for example, be disgusted by the smell of raw food, repulsed by the smell of food that is cooking, and repelled by food that doesn’t bother you at other times. You might feel that many foods are rotten, or you may detect the persistent smell of food on your hands or in your surroundings.
This can manifest with physiological symptoms such as anxiety and migraine.
The response to the smell may be inconsistent. Certain scents, such as those from polishes and chemical cleaners, may seem exceedingly strong when you are having a migraine but be entirely benign at other times.
Osmophobia is a common psychological feature of a migraine attack, just like photophobia (sensitivity to light) and phonophobia (sensitivity to sound).
The Role of Hyperosmia
In contrast, hyperosmia is when disease, pregnancy, nutritional deficiencies, or an adverse reaction to a medication causes smell hypersensitivity.
Hyperosmia and osmophobia can work together to induce a migraine attack. Because hyperosmia causes smell hypersensitivity, it can induce a psychological response in the form of osmophobia.
Scent hypersensitivity from hyperosmia could be related to the size of the olfactory bulb (the receptor in the brain that processes signals from the nose).
Some studies have suggested that people who get migraines are more likely to have a smaller olfactory bulb than people don’t. Others have reported that people with migraines and osmophobia have an even smaller olfactory bulb volume.
Some researchers suggest that diminished blood flow to the olfactory bulb could be the cause of shrinkage of this organ. However, these structural changes are subtle, and measuring your olfactory bulb is not a standard procedure.
Common Odor Triggers
Smells are just as powerful a trigger for migraines as alcohol and sleep deprivation.
There are a variety of odors known to precipitate migraines, the most common of which include:
Car exhaustGasolinePesticidesPerfumesNail polishCigarette smokeCooking smokeBleachAsphaltSolvents and detergents
Odors are more likely to induce a migraine if you are exposed for more than 15 minutes and if you are in an enclosed space.
Prevention Tips
Awareness and avoidance of your migraine triggers are key to improving your quality of life. There are several steps you can take to thwart scent-induced migraines.
Recognize When You’re Triggered
It may be hard to think back on your day and try to align where you were and what you were doing when a migraine started or worsened.
But at least 50% of people who have recurrent migraines experience premonitory symptoms, which occur during the first (prodromal) stage of a migraine.
If you notice symptoms such as moodiness, dizziness, or fatigue, take note of your surroundings and activities in that moment.
Do you tend to have migraines while you are in certain locations?Do they occur when you are doing particular things like cooking or cleaning the house?
Then try to see if there is a pattern between this and the onset of your migraines over time.
Control Your Environment
When you are exposed to fumes that could trigger a migraine, leave where you are, open a window, or step outside if you can.
If you work closely with paint thinners, gasoline, or odorous substances that you are sensitive to, consider switching to another workspace where you better able to avoid these smells.
Some people experience a condition known as sick building syndrome, characterized by a variety of symptoms caused by chemicals in an enclosed environment. Good circulation can help prevent migraines and can keep your workplace healthier for everyone.
A Word From Verywell
Living with migraines requires adapting your mindset and making adjustments when you need to. Sometimes, putting up with certain things—such as odors—can help you avoid a migraine by lowering your stress levels.
