Nausea is the most informative thing your headache does.

WHAT COMES WITH IT · NAUSEA

A headache with nausea is most often migraine. In migraine, the nausea and the pain both come out of the same attack. Some patterns need prompt assessment: vomiting with little nausea, or nausea with fever, a stiff neck or new neurological change.

Nausea is the single most useful side symptom in headache. When it is there, it moves you firmly toward one diagnosis. When it is missing, that diagnosis becomes clearly less likely.

Why does a headache with nausea usually mean migraine?

Migraine is not a headache with nausea attached. It is a whole-brain event, and the nausea and the pain are both outputs. The brainstem centers that control nausea switch on as part of the attack. That is why the nausea can come hours before the pain. It is also why some people have the nausea without much headache at all.

Tension-type headache, by contrast, is defined partly by the lack of significant nausea. So “my tension headaches make me feel sick” is usually a migraine going by another name. That wrong label has real costs, because the treatments differ.

Why don’t pills work well when a headache makes you nauseous?

During an attack, nausea and gastric stasis (a stomach that stops emptying) slow the uptake of anything swallowed. That is why a tablet taken late in an attack often fails. The drug is not failing. It is not getting absorbed (a pharmacokinetic failure). But people decide the medicine does not work for them, and they step it up. Timing and route matter as much as the drug itself. Raise this directly instead of deciding you are treatment-resistant.

The knock-on cost is the same one that runs through this site. Stepping up abortives (attack-stopping drugs) again and again adds medication days. Past ten days a month of certain classes, the treatment starts keeping the pattern going. How that unwinds.

Frequently asked questions

Does nausea mean it is a migraine?

It makes migraine clearly more likely, and its absence makes it less likely. It is not proof on its own. But it is the most telling single side symptom.

Why does my medication stop working during a bad attack?

Often because the stomach slows its emptying and the tablet is not absorbed. That is a timing and route problem, and it can be fixed — raise it specifically.

I get the nausea without much headache. Is that a thing?

Yes. Migraine can show up with the side symptoms in the lead and little pain. That is a common reason it goes unrecognized for years.

When is vomiting with a headache an emergency?

When it comes with little nausea, when it is worse lying flat or on waking, or when it comes with any neurological change — see the alert box and the red-flag page.

What causes a headache with nausea?

Most often migraine. In a migraine attack, the brainstem centers that control nausea switch on as part of the attack itself. So the nausea and the pain are two outputs of the same event. That is why the nausea can start hours before the pain. It is also why some people feel sick with very little headache at all.

Can a tension headache cause nausea?

Not significant nausea. Tension-type headache is defined partly by the absence of it. So a headache people call a tension headache that makes them feel sick is usually a migraine going by the wrong name. The label matters because the two are treated differently. A wrong label means the wrong plan.

How do I know if my nausea fits a migraine?

It arrives with, or shortly before, a one-sided throbbing headache. It comes with sensitivity to light and sound and a wish to lie down in the dark. Routine movement makes it worse. It settles as the attack settles, and you have well days in between attacks. Nausea that follows this pattern points firmly to migraine.

When should I worry about a headache with nausea?

Get prompt assessment when the pattern does not fit migraine. Watch for vomiting with little nausea beforehand, especially on waking or lying flat. Watch for nausea with fever and a stiff neck. Watch for nausea with confusion, new weakness or vision loss. And watch for a sudden, severe, worst-ever headache. Those belong on the emergency list, not in a wait-and-see plan.

Also worth reading

• Light and sound sensitivity
• Migraine
• Vision changes
• Medication overuse
• The emergency list