Migraine

Migraine is a disorder of the brain in its own right. Between attacks the brain works normally; during one, systems that control pain, light, sound and nausea are all disturbed together, and that is why a bad attack is so much more than a headache.

An attack tends to move through stages. Hours or even a day beforehand many people have a warning phase of yawning, food cravings, neck stiffness or a shift in mood and energy, and it is recognisable once you know to look for it. Some people then get an aura: a visual disturbance that builds over twenty to sixty minutes, often zigzag lines or a spreading blind spot, or numbness creeping up an arm into the face. The headache follows, commonly on one side and throbbing, made worse by ordinary movement, and it runs from four hours to three days if it is not treated. Afterwards comes a day of feeling wrung out.

Triggers get most of the blame and deserve some of it. Missed meals, too little or too much sleep, dehydration, alcohol, the let-down after a stretch of stress and, in many women, the fall in oestrogen before a period are the usual ones. A single trigger rarely does it on its own; several stacked in the same week usually will. Keeping a simple diary of attack days for two or three months is the most useful thing you can bring to the appointment.

There is no blood test and no scan that shows migraine, so the diagnosis is made from your account of the attacks. Your doctor will want to know how long an untreated attack lasts, what you cannot do while it is happening, what comes before and after it, how many days a month you are affected, and how many days a month you take a painkiller. That last number changes the plan more often than anything else.

The examination that follows is there to make sure nothing else is going on. Your doctor checks your blood pressure, looks at the back of your eyes, tests eye movements, power, sensation, coordination and balance, and feels the neck and scalp. A normal examination alongside a typical history is what lets the diagnosis be made with confidence and without imaging.

Scans are ordered for particular reasons and not as reassurance. A headache that reached full intensity within seconds, a pattern that has clearly changed, a first migraine-like headache after fifty, a headache that is worse lying flat or on coughing, fever with a stiff neck, or any abnormality found on examination will all prompt one.

A single attack treated at the first sign usually breaks within a few hours. The same attack treated three hours in, once it is established, can run the whole day. Taking the acute medicine early instead of waiting to see how bad it gets is the single change that makes the most difference for most people, and it means carrying it with you.

Where attacks are frequent enough to warrant something taken every day to reduce them, give it eight to twelve weeks at an adequate dose before you judge it. The dose is usually built up slowly to limit side effects, so the first few weeks are not a fair test. The target is fewer and milder attacks, and expecting every attack to stop is what leads people to abandon a treatment that was working. Most of these are continued for six to twelve months and then reduced.

Where headaches have been driven by taking painkillers too often, the sequence is different and worth knowing in advance: things get worse for one to two weeks after the painkillers are cut back, then improve over the following four to twelve weeks. Your doctor will plan that with you and will usually start something preventive at the same time.