Osmophobia

Osmophobia or olfactophobia refers to a fear, aversion, or psychological hypersensitivity to odors. Osmophobia seems to be a consistent part of the patient’s migraine history, but additional criteria are needed to differentiate it from episodic tension-type headache (ETTH). ^[1] The phobia generally occurs in chronic migraine sufferers who may have odor triggered migraines.^[2][3]

Such migraines are most frequently triggered by foul odors, but the hypersensitivity may extend to all odors. One study found as many as 25% of migraine sufferers had some degree of osmophobia.^[4] The condition may also be present in individuals in substance withdrawal, specifically opioid withdrawal syndrome, where it is usually associated with nausea and/or vomiting.

The term osmophobia comes from the Greek ὀσμή (osmḗ), meaning "smell, odour",^[5] and φόβος (phóbos), meaning "fear".^[6] Olfactophobia comes from the Latin olfacto, meaning "to smell at".^[7]