Neurological symptoms that manifest as visual hallucinations, like flashing lights, sparks, or lines (followed by dark spots), facial tingling or numbness, and possibly including other sensory, motor, or aphasic symptoms that usually last from 5 minutes to an hour.1

calcitonin gene-related peptide (CGRP)

Calcitonin gene-related peptide, or CGRP, is a neuropeptide that is abundant in the trigeminal system. CGRP is known to play a role in the transmission of signals that can cause incapacitating pain through processes including vasodilation, inflammation, neuropeptide release, and nociceptor sensitization.2,3

central nervous system

One of the two main parts of the nervous system (the other being the peripheral nervous system), the central nervous system refers to the nerves in the brain and the spinal cord.4

chronic migraine

A patient will receive a diagnosis of chronic migraine (CM) if they have experienced ≥ 15 headache days/month (tension type and/or migraine) for > 3 months and their headaches have features of migraine for ≥ 8 days/month.5

episodic migraine

A patient will receive a diagnosis of episodic migraine (EM) if they have a history of ≥ 4 migraine attacks and their headaches occur at a frequency of < 15 days/month.2,6

migraine-affected days

An overarching term used to collectively define all 3 phases of migraine—premonitory (pre-migraine), migraine attack, and postdrome (migraine hangover).

migraine attack

Also known as “migraine pain” or a “migraine episode,” this is the second phase of migraine. During this phase, patients will experience acute unilateral head pain that can last from 4 to 72 hours.7


Relating to both the nerves and the blood vessels.8

peripheral nervous system

One of the two main parts of the nervous system (the other being the central nervous system), the peripheral nervous system refers to the nerves outside of the brain and spinal cord.4


A feature of migraine where patients experience an abnormal sensitivity to noise.9


A common feature of migraine, where normal levels of light are perceived as unpleasant or painful.10,11

postdrome (also known as migraine hangover)

Also referred to by patients as the “migraine hangover” this is the final stage of a migraine. It is characterized by symptoms that arise or persist after migraine pain has resolved, such as fatigue, weakness, and cognitive symptoms. This phase can last up to 24 hours.2,7,12

premonitory (also known as pre-migraine)

Premonitory, also referred to as “pre-migraine” or “prodrome,” is the first of 3 phases of a migraine. During this phase, the first symptoms or signs of migraine begin, such as changes in activity, fatigue, food cravings, repetitive yawning, stiff neck, phonophobia, and in some cases aura. This phase can last up to 48 hours.7,11

trigeminal system

This system centers on the trigeminal nerve, which is responsible for carrying the majority of afferent pain information from structures above the tentorium cerebelli.2,13


The widening of the lumen blood vessels due to muscle relaxation in the vessel wall. Vasodilation leads to increased blood flow.14,15


1. Viana M, Sprenger T, Andelova M, Goadsby PJ. The typical duration of migraine aura: a systematic review. Cephalalgia. 2013;33(7):483-490. 2. Russo AF. Calcitonin gene-related peptide (CGRP): a new target for migraine. Annu Rev Pharmacol Toxicol. 2015;55:533-552. 3. Goadsby PJ, Lipton RB, Ferrari MD. Migraine — current understanding and treatment. N Engl J Med. 2002;346(4):257-270. 4. Medical definition of central nervous system. Accessed May 9, 2017. 5. Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia. 2013;33(9):629-808. 6. Blumenfeld AM, Varon SF, Wilcox TK, et al. Disability, HRQoL and resource use among chronic and episodic migraineurs: results from the International Burden of Migraine Study (IBMS). Cephalalgia. 2011;31(3):301-315. 7. Goadsby PJ, Holland PR, Martins-Oliveira M, Hoffmann J, Schankin C, Akerman S. Pathophysiology of migraine: a disorder of sensory processing. Physiol Rev. 2017;97(2):553-622. 8. MedlinePlus. Neurovascular. Accessed May 9, 2017. 9. MedlinePlus. Phonophobia. Accessed May 9, 2017. 10. Medical definition of photophobia. Accessed May 9, 2017. 11. D’Amico D, Tepper SJ. Prophylaxis of migraine: general principles and patient acceptance. Neuropsychiatr Dis Treat. 2008;4(6):1155-1167. 12. Charles A. The evolution of a migraine attack - a review of recent evidence. Headache. 2013;53(2):413-419. 13. Wrobel Goldberg S, Silberstein SD. Targeting CGRP: a new era for migraine treatment. CNS Drugs. 2015;29(6):443-452. 14. Medical definition of vasodilation. Accessed May 9, 2017. 15. Gasparini CF, Sutherland HG, Griffiths LR. Studies on the pathophysiology and genetic basis of migraine. Curr Genomics. 2013;14(5):300-315.