abortive medicine: Medicine taken to treat the symptoms of a headache.

Adrenal: A stress hormone.

Analgesics: Painkilling medicines.

Anticonvulsants: Medications used to treat seizures and also used to prevent headaches.

Antidepressants: Medications used to treat depression and also used to prevent headaches.

Antivasospastic action: An action that prevents arteries from going into a spasm, as well as inhibiting the constriction and dilation of blood vessels that leads to headaches.

Aura: Avisual disturbance that occurs before a migraine attack in some patients.

Ayurveda: Traditional Indian medicine.

Beta blockers: A medication used to aid in headache prevention.

Calcium channel blockers: A medication used to aid headache prevention.

Chronic headaches: Headaches that recur at least three times a month over a period of months or years.

Cluster headaches: An extremely painful type of primary headaches. These headaches occur in quick succession.

Cortisol: A stress hormone.

Endorphin: A natural chemical produced by...