OsteoVShimmering zigzags that drift across your vision. A blind spot where a face should be. Tingling that creeps up your hand towards your mouth. If your migraine sometimes announces itself before the pain arrives, that warning act has a name: aura. Here is what is actually happening, in plain language, and why it is worth telling your clinician about.
What aura actually is
Around a third of people with migraine experience aura, and many of them only in some attacks. It is not a problem with your eyes, even when the symptoms are visual. Aura is a brain event: a slow wave of altered electrical activity that spreads across the surface of the brain, temporarily changing how the affected area works as it passes.
That slowness is the giveaway. Aura symptoms typically build gradually over five minutes or more, and each symptom usually lasts between five minutes and an hour before fading. The headache often follows within the hour, though not always. That gradual spread matters, because symptoms that arrive suddenly and all at once deserve a different, more urgent conversation.
What it can look and feel like
Visual aura is by far the most common form, affecting over 90% of people who get aura at all. Classic descriptions include a shimmering arc of zigzag lines that grows and drifts across the visual field, blind spots, sparkles or flashing lights. Whichever eye you cover, it is still there, because it is happening in the brain rather than the eye.
Aura can also be sensory: a tingling or numbness that starts in the fingers and slowly spreads up the arm to the face or tongue. Some people have trouble finding words or getting sentences out. These symptoms are frightening the first time, and being frightened by them is a reasonable response, not an overreaction.
Aura without the headache
Some people get the light show without the main event. Aura symptoms with no headache afterwards are sometimes called silent migraine, and this pattern becomes more common as people get older. If you had migraine with aura in your twenties and now get odd visual episodes with no pain in your forties or fifties, that may be the same condition in a new costume. It still deserves assessment, particularly the first few times, because new visual symptoms should never simply be assumed to be migraine.
Why aura changes the plan
Here is the part that too often goes unsaid in a rushed appointment. If you have migraine with aura, it matters for your contraception. UK guidance advises against combined hormonal contraception, which is the pill, patch or ring containing oestrogen, for women with migraine with aura, because the combination is associated with a higher risk of ischaemic stroke.
The absolute risk is still small. One NHS patient resource puts it at around 28 strokes per 100,000 women per year in combined-pill users with aura, compared with about 5 per 100,000 without migraine. But it is a risk that can be avoided, and progestogen-only methods, which do not carry the same association, work well for many women. This is a conversation to have with your GP or contraception clinic, not a reason to stop anything on your own. If nobody has ever asked you whether your migraine comes with aura before prescribing, that question is worth raising yourself.
When aura needs a proper check
Aura can mimic more serious things, and more serious things can mimic aura. Get medical assessment promptly if aura symptoms appear for the first time, especially over the age of 50, if they arrive suddenly rather than building gradually, if they last longer than an hour, or if they include weakness down one side. Most of the time the answer is reassuring. The point of checking is to earn that reassurance properly.
When to seek urgent care
See a doctor promptly, or call 999, if you have a sudden, severe "thunderclap" headache, a headache with fever and a stiff neck, new weakness, numbness, confusion or speech difficulty that comes on abruptly, or a headache after a head injury. New or changing neurological symptoms always deserve medical assessment.
If your attacks come with aura, or with strange symptoms nobody has ever explained to you, a thorough assessment can put a name to what is happening and shape a plan around it. You are welcome to book an appointment or get in touch.
- The Migraine Trust. Migraine with aura. themigrainetrust.org
- International Classification of Headache Disorders, 3rd edition (ICHD-3), section 1.2: Migraine with aura. ichd-3.org
- Sacco S et al. Hormonal contraceptives and risk of ischemic stroke in women with migraine: consensus statement from the European Headache Federation and the European Society of Contraception and Reproductive Health. J Headache Pain, 2017.
- Faculty of Sexual and Reproductive Healthcare (FSRH). UK Medical Eligibility Criteria for Contraceptive Use (UKMEC). fsrh.org
- Oxford Health NHS Foundation Trust. Migraines and combined hormonal contraceptives, patient information leaflet.