• Migraine without aura: a throbbing headache at the front or side of the head (usually on one side), moderate to severe pain with nausea and vomiting, sensitivity to bright light, and worsened by head movements
• Migraine with aura: has the features of migraine without aura, but there is also a warning sign (known as aura) at the start of the headache. The aura may be visual (e.g., flashing lights, zig-zag lines, or partial loss of vision) or a sensation (e.g., numbness, a speech problem, or a smell)
• Migraine with aura without headache: has the feature of a migraine with aura but without the onset of headache

Furthermore, a migraine can be divided into four phases. First is the premonitory phase when you may feel depressed, tired and irritable or have food cravings; then comes (if it is to happen) the aura; then the headache; and finally, resolution when the headache disappears.

Migraine is one of the most common health conditions in the world. More women than men have migraine attacks, with migraine reported in approximately 1 in 5 women and 1 in 12 men. Migraine can begin at any age, but usually attacks begin in the teenage years. Over half of migraineurs (people with migraine) have one or more attacks a month, and more than 1 in 10 report one or more attacks a week.

Migraine is about how a person’s brain deals with sensory information, such as pain, light or sound. Migraineurs have a very sensitive nervous system, particularly to change. Chemical changes in the brain cause the attack to start, which leads to a chain of events that result in the brain responding abnormally to normal signals (e.g., light sensitivity, visual disturbances, dizziness, or numbness or tingling). Narrowing and opening of blood vessels in the brain may also play a role. Migraine often runs in families so you may have inherited genes linked to migraine.

Differences within the body can make individuals more prone to migraine but other ‘outside’ things are important in causing migraine attacks. Being unpredictable, migraine can be ‘triggered’ by numerous things, including:

• Foods, e.g., chocolate, cheese, red wine, citrus fruits
• Psychological factors, e.g., stress, anxiety, depression, tiredness
• Environment, e.g., high altitude or humidity, noise, flickering lights
• Foods containing caffeine, or food additives (e.g., tyramine)
• Sleep (too much or too little)
• Drugs, e.g., oral contraceptives, sleeping pills
• Lack of food or irregular meals
• Change in routine
• Hormonal changes in women
• Mild dehydration
• Exercise

But it’s not that simple, because it is not usually possible to say that this or that causes migraine. While trigger factors certainly play a role if you are predisposed to migraine, it may be useful to keep a migraine diary with details of your migraine (e.g., when it started/ended, and symptoms) and aspects about your daily life (e.g., what you ate/drank, medication, exercise, sleep, and menstrual cycle). You may be able to determine a pattern and avoid any culprits.