Believe it or not, odor plays a role in triggering migraines and may signal the first phase of a migraine attack

Increased sensitivity and intolerance to smells, medically known as osmophobia, 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.

It is not clear, though, why some people are more sensitive to noxious smells. But if you are predisposed to migraines, you are more likely to experience migraines and non-migrainous headaches when you are exposed to strong smells. Headaches triggered by odors tend to be severe and are often accompanied by nausea.

Common Odors That Trigger Migraines

There are a variety of odors known to precipitate migraines. The most common include:

  • Car exhaust
  • Pesticides
  • Perfume
  • Nail polish
  • Cigarette smoke
  • Cleaning products

If you have recurrent migraines, exposure any of these scents can be enough to cause an episode.

Other examples of odors that may trigger a migraine include:

  • Asphalt
  • Carpeting
  • Paint or paint thinners
  • Detergents
  • Leather
  • Combustible gas

Odors are more likely to induce a migraine if you are exposed for a prolonged period of time (more than 15 minutes) and if you are in an enclosed space.

Preventing Odor-Induced Migraines

Awareness and avoidance of your migraine triggers are key to improving your quality of life. There are several steps you can take to thwart olfactory-induced migraines:

Recognize Your Triggers

Be observant. Do you tend to have migraines when you are in certain locations? You could be extra sensitive to the fumes in these settings.

Take Note of Premonitory Symptoms

At least 50 percent 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 before your migraines, you can try to avoid the fumes that bother you during this time.

Get Some Fresh Air

When you are exposed to fumes that could trigger a migraine, leave the environment, open a window, or step outside if you can.

Take Charge of Your Environment

For example, if you discover that perfume is one of your migraine triggers, consider discussing a perfume-free space with your boss or roommate. Some people experience a condition known as sick building syndrome, which is characterized by a variety of symptoms related to chemicals in an enclosed environment. Good circulation and avoidance of too many noxious substances can help prevent your migraines and can keep your workplace healthier for everyone.

Adapt Your Lifestyle

If you work closely with paint thinner, gasoline, or another odorous substance that you are sensitive to, consider switching to another work setting where you can avoid these exposures.

Heightened Sense of Smell and Aversions

During a migraine, you may notice an amplified sense of smell or a sense that certain odors are unpleasant. This phenomenon is called osmophobia, and the vast majority of migraineurs experience it at some time or another during the premonitory phase according to the American Migraine Foundation.  

Why Osmophobia Occurs

Interestingly, this hypersensitivity and aversion to smells could be related to a diminished size of the olfactory bulb (the receptor in the brain that processes input of odors). Small studies have suggested that people with migraines seem to have a smaller olfactory bulb than people without migraines and that people who have both migraines and osmophobia have an even smaller olfactory bulb volume.

Osmophobia can be particularly unpleasant and may occur during all stages of a migraine which can make the migraine experience even more painful. You may be disgusted by the smell of raw food, repulsed by the smell of food that is cooking, and repelled by food that normally does not bother you.

This classically occurs during a migraine attack, just like photophobia (sensitivity to light) and phonophobia (sensitivity to sound) along with other prodrome symptoms outlined in our previous post about The Six Warning Signs of a Migraine Headache.

 If you experience migraine attacks, click here to sign up to participate in a paid migraine research study with Boston Clinical Trials.