Sensitivity to Smells
Reviewed by: HU Medical Review Board | Last review date: December 2019 | Last updated: October 2020
Migraine can mean more than head pain. For instance, many people can become sensitive to smells before, during, or after a migraine attack. Smells may also trigger a migraine or make it worse. Odors known to trigger migraine include perfume, cigarette smoke, car exhaust, cleaning products, and certain foods.1
What is that smell?
Hyperosmia is the medical term for sensitivity to smell. About 95 percent of people living with migraine are sensitive to smells.1 Sensitivity to smell has not been studied as much as migraine aura or light sensitivity. But it happens often and can be distracting or cause nausea as another symptom.
In some people, the change may be a small increase in the ability to smell things far away. In other people with migraine, smells may trigger an attack or increase its severity. Some also report increased sensitivity to smells in between migraine attacks.2
More women with migraine report sensitivity to smells than men.3
How does sensitivity to smell impact people with migraine?
Sensitivity to smell may take different forms before, during, and after a migraine, including:
- Increased sense of smell
- Need to avoid smells
- Increased nausea
- Changes in both taste and smell
- May act as a migraine trigger
What are phantom smells?
A small number of people report sensing smells that other people cannot smell before, during, or after their migraine. These are called phantom smells or olfactory hallucinations. This rare symptom occurs more often in children than in adults.1
Why does sensitivity to smell occur with migraine?
Doctors do not understand why sensitivity to smell is linked to migraine attacks. Migraine may activate brain cell pathways that change sensory processing, and this may change how people perceive smells.4
Processing of smells involves the limbic system of the brain, the area that controls emotions and hunger and sex drives. People with migraine show more activity in the limbic system during a migraine attack than in between attacks.2
How is smell sensitivity treated?
If you learn that sensitivity to smell is one of your usual migraine symptoms, you may be able to treat the attack sooner. Early migraine treatment in prodromal (pre-attack) phase can reduce the pain and other symptoms.
Other steps you can take if you have identified that smells can trigger your migraine attacks:
- Limit scents in your house, such as asking guests to avoid perfume and scented body products.
- Ask for a scent-free environment at work.
- If someone is cooking during your migraine attack, try to open up a window to let fresh air in and get rid of any smell.
Do certain smells bother you only during a migraine attack?
Tracking your migraine symptoms
Keeping a record of your migraine symptoms may help you figure out patterns and triggers to your attacks. It may be helpful to record such things as:
- When and where your pain or symptoms start
- Whether the pain spreads to your entire head or neck
- How well and how quickly acute treatment helps reduce the pain or other symptoms
- How long your pain or symptoms last
- Whether you experience other symptoms such as vision changes, nausea, or light sensitivity
Community experiences of sensitivity to smell
Migraine.com advocates share their experiences of migraine, including sensitivity to smells. In this "What's Your Secret: Smells" video, the many ways odor can interact with migraine is discussed. Various tips on how to avoid odors include alternative cleaning products, shopping for make up, and how to manage the scent overloaded holidays. Avoiding scent triggers can be tricky when an odor is ok one day but not the next but our advocates are always sharing their tips including home-made remedy tools.