"Headache" is not a diagnosis. It's a symptom shared by more than three hundred distinct conditions in the international classification, and the three that account for most of them respond to completely different things.
Getting the category right is not academic. It determines whether prevention is worth attempting, whether the treatment you need is available over a counter or only on prescription, and in one case whether you have a condition that is routinely missed for years while being one of the most severe pains in medicine.
Here is how the International Classification of Headache Disorders (ICHD-3) separates them, and what each distinction actually buys you.
For migraine without aura, ICHD-3 requires at least five attacks lasting 4 to 72 hours untreated, with:
At least two of these four pain features — one-sided location · pulsating quality · moderate or severe intensity · aggravation by routine physical activity such as walking or climbing stairs.
And at least one of these — nausea and/or vomiting · or photophobia and phonophobia together.
Two details in there do a lot of work.
The five-attack requirement. Migraine is a pattern, not an event. One severe headache, however unpleasant, doesn't meet the definition — and a genuinely new severe headache is a reason to be assessed rather than to self-diagnose.
“Aggravated by routine physical activity.” This is the criterion people underrate, and it's the one that separates migraine from almost everything else in seconds. Someone mid-migraine wants to lie completely still in a dark room. Stairs make it worse. Bending forward makes it worse. This is why migraine is so often invisible to other people — the sufferer has removed themselves.
A migraine attack is not just the headache. It commonly runs in phases, and knowing them changes what you can do about it.
Prodrome — hours to a day or two beforehand. Yawning, mood change, neck stiffness, food cravings, unusual thirst, difficulty concentrating. Most people have a prodrome and don't recognise it as part of the attack.
Aura — experienced by roughly a quarter to a third of people with migraine, and not by the rest. Typically visual: a small shimmering or zigzag disturbance that expands across the visual field over 5 to 60 minutes. It can also be sensory (pins and needles spreading up an arm) or affect speech. The underlying event is thought to be a slow wave of altered electrical activity moving across the cortex, which is why aura spreads rather than appearing all at once.
Headache — the phase everyone knows.
Postdrome — the "migraine hangover." Fatigue, difficulty concentrating, a wrung-out feeling that can last a day after the pain has gone. Frequently mistaken for the after-effects of medication or of a bad night.
Trigger lists circulate endlessly: chocolate, cheese, red wine, stress, weather.
Some are real. But a meaningful number of classic "triggers" are better explained the other way round. Craving chocolate is a recognised prodrome symptom. If the attack has already begun and the prodrome makes you want something sweet, then eating chocolate and getting a migraine four hours later looks exactly like cause and effect while being nothing of the kind.
The practical consequence is that people eliminate foods for years on the strength of a pattern that was running backwards. A headache diary that records the day before as well as the day of an attack is the only way to tell the difference.
Tension-type headache is the most common headache disorder there is, and its criteria read almost as the exact inverse of migraine's.
Duration 30 minutes to 7 days, with at least two of — both sides · pressing or tightening rather than throbbing · mild or moderate intensity · not aggravated by routine activity.
Plus no nausea or vomiting, and no more than one of photophobia or phonophobia.
Bilateral not unilateral. Pressing not pulsating. Unaffected by movement rather than worsened by it. Little or nothing accompanying it.
The classification also grades it by frequency — infrequent episodic (fewer than one day a month on average), frequent episodic, and chronic. That frequency ladder matters, because a tension-type headache that has become near-daily needs a different conversation from one that shows up occasionally, and raises the question of medication overuse.
Duration 15 to 180 minutes untreated. Pain severe or very severe, strictly one-sided, around or behind the eye, in the temple, or above the eye socket.
Plus at least one autonomic feature on the same side — red or watering eye · blocked or running nostril · swollen eyelid · sweating on the forehead or face · a constricted pupil or drooping eyelid.
Or a sense of restlessness or agitation.
Frequency from one attack every other day up to eight a day, over a bout.
This single feature separates cluster from migraine faster than anything else. Migraine makes people lie still. Cluster makes people unable to. The typical description is pacing, rocking, hitting the head against something, being unable to remain in a chair. It is the opposite behaviour, driven by the opposite instinct.
Two more characteristics are worth knowing because they're diagnostic in practice. Cluster attacks are strikingly circadian — they tend to recur at the same time each day, often waking people at night. And the bouts themselves are often seasonal, arriving in the same weeks each year with long remissions between.
Cluster headache is comparatively rare, and it is frequently misdiagnosed for years as sinus problems, dental problems or migraine. That matters because it has specific treatments that work — high-flow oxygen and injectable or nasal triptans for attacks, and preventive options for bouts — and none of them are things you'll arrive at by treating it as a bad migraine.
MigraineTension-typeClusterDuration4–72 hours30 min – 7 days15–180 minutesLocationUsually one sideBoth sidesOne side, around the eyeQualityPulsatingPressing, tighteningSevere, boring, drillingIntensityModerate to severeMild to moderateSevere to very severeMovementMakes it worse — lie stillNo effectCan't keep stillAccompanied byNausea, light and sound sensitivityLittle or nothingWatering eye, blocked nose, drooping lidPatternEpisodic, sometimes with auraEpisodic to chronicDaily bouts, often seasonal
These mean urgent medical attention rather than a category:
Sudden weakness, numbness or trouble speaking alongside a headache is stroke territory — an emergency call, not a headache category.
Migraine has a genuine prevention strategy. Prescription preventives, the newer CGRP-targeting treatments which changed the field considerably, sleep regularity, and a modest evidence base around specific supplements at specific doses — which we've written up honestly, including where our own range falls short of the studied dose. The magnesium evidence in migraine sits in much the same place: real, modest, and dependent on taking enough for long enough.
Tension-type generally tracks load, posture, sleep and stress. Where poor sleep is the driver, CBT-I is the intervention with the strongest evidence. It responds to addressing those, and it does not respond to migraine-specific treatment, which is one reason misclassification wastes years.
Cluster needs a doctor, and specifically needs someone to consider it. If the pattern above is familiar — one side, around the eye, can't sit still, same time each day, in bouts — say those words at the appointment. They are the ones that prompt the right referral.
If you have headaches on most days and reach for painkillers often, the painkillers themselves may now be part of the problem. Medication-overuse headache has its own specific criteria — and the way out of it is counter-intuitive enough that it needs a doctor rather than a decision.
Proco sells supplements. None of them treats migraine, tension-type headache or cluster headache, and we're not going to imply otherwise. The most useful thing this article can do is get you into the right category, because that is what determines which of the genuinely effective options applies to you.
One pattern worth ruling out separately: a headache present on waking that eases through the morning, alongside unrefreshing sleep and daytime sleepiness, can point to obstructive sleep apnea rather than a primary headache disorder — and that has an entirely different answer. Persistent headache alongside fatigue also justifies a short list of blood tests, since iron deficiency and thyroid dysfunction both produce it.
Diagnostic criteria summarised from the International Classification of Headache Disorders, 3rd edition. This article is not medical advice and cannot diagnose a headache disorder.