Headaches: which ones need a scan, and which ones need a routine

The question I am asked most often is whether a headache means there is a tumour. It is a reasonable fear and the answer is almost always no — but 'almost always' is not a satisfying thing to hear, so it is worth explaining how we decide, because the decision is made on the story rather than the scan.

The two headaches nearly everyone has

Tension-type headache

A band of pressure around the head, or tightness at the back of the neck and shoulders. Mild to moderate, both sides, no nausea, and it does not stop you functioning. It builds through a long day, and is worsened by poor sleep, stress, dehydration, skipped meals and hours at a screen with the neck in one position.

Migraine

Usually one-sided and throbbing, moderate to severe, made worse by ordinary movement, and accompanied by nausea and a strong dislike of light and sound. It lasts hours to a few days. Some people get an aura first — flickering zigzags, a blind spot, or tingling spreading up one arm — for twenty minutes or so before the pain. Many are left washed out for a day afterwards.

Migraine is not a small thing. It is one of the leading causes of disability worldwide, it is under-diagnosed here, and it responds well to treatment when it is named correctly. Being told 'it is only a migraine' is a failure of communication, not a diagnosis.

The headaches that need imaging

These features are why a scan gets ordered. They are worth learning because most people can recognise them in themselves.

• A thunderclap headache — maximum severity within a minute, the worst of your life. This needs an emergency department the same hour.
• A new headache after the age of fifty
• A headache that has changed in pattern, character or severity from your usual one
• A headache that is progressively worsening week by week rather than coming and going
• One that is worse in the morning, or wakes you from sleep, or is made worse by coughing, straining or bending forward
• Any headache with neurological signs: weakness, numbness, difficulty speaking, unsteadiness, double vision, or a persistent visual change
• A headache with fever and a stiff neck, or with a rash
• A new headache in pregnancy, in someone with cancer, or in anyone with a weakened immune system
• A headache after a head injury, particularly with vomiting or drowsiness

The cause we find most often, and the one nobody expects

Medication-overuse headache. If you take painkillers for headache on more than about ten to fifteen days a month, the medicines themselves begin to generate a daily background headache. It is a genuine, well-described phenomenon, and it is common here where combination painkillers are bought freely.

The pattern is unmistakable once you look for it: a daily or near-daily headache, present on waking, briefly relieved by a tablet, returning as it wears off. The treatment is to come off the offending medicine — usually with support and a preventive drug to cover the withdrawal period, because the first two weeks are genuinely unpleasant. People who get through it very often go back to having occasional headaches rather than constant ones.

“If you are reaching for a painkiller more than two days a week for headaches, the painkiller has become part of the problem.”

What actually helps

1. Keep a headache diary for six weeks: date, duration, severity, what you took, and what preceded it. It is the single most useful thing you can bring to a consultation, and it usually identifies triggers no one had suspected.
2. Fix the boring things first — a consistent sleep schedule including weekends, meals at regular times, and enough water. In summer here, dehydration alone accounts for a great many headaches.
3. Treat an attack early and adequately. A proper dose at the first sign works far better than a small dose two hours in.
4. If you have four or more disabling headaches a month, ask about preventive treatment. Taken daily, these reduce how often attacks happen — they are not painkillers and they are not addictive, and they are badly underused.
5. Set up your screen: top of the monitor at eye level, and a twenty-second break every twenty minutes. Also have your eyesight checked; uncorrected refractive error is a real and easily fixed cause.

If your headaches are stopping you working, studying or sleeping, that alone is reason enough for a consultation — regardless of whether any red flag applies. Disability is a legitimate indication for treatment.