Extract: The hypothesis that trace amines such as tyramine, octopamine, and synephrine, closely related chemically
to classic biogenic amines,1,2 may contribute to the pathogenesis of primary headaches was proposed several decades ago.3,4 The observation that certain foods rich in tyramine, such as chocolate, citrus fruits, and cheese, caused a hypertensive headache response in depressed patients treated with monoamine oxidase (MAO) inhibitors raised the possibility that the increased sensitivity to tyraminecontaining foods in dietary migraine might be due to a deficiency in MAO activity.