Can Migraines Cause Syncope (Fainting)?

Migraines can and do increase the risk of fainting. In a large population-based study, people with migraine reported a lifetime prevalence of syncope of about 46%, compared with 31% among people without migraine. The connection runs deeper than coincidence: the two conditions share overlapping nervous-system mechanisms that make the brain of someone with migraine more vulnerable to the sudden blood-pressure drops that cause blackouts. The relationship is well-documented enough that researchers have even proposed “syncopal migraine” as a distinct clinical pattern.

How Common Is Fainting Among People With Migraine

The most cited numbers on this topic come from the CAMERA study, a Dutch population-based investigation that compared migraine sufferers to matched controls. People with migraine were significantly more likely to have fainted at some point in their lives, with a prevalence of 46% versus 31% in controls. The gap widened for people who fainted repeatedly: about 13% of migraineurs reported five or more syncopal episodes, compared with just 5% of controls. Orthostatic intolerance, the feeling of lightheadedness or near-fainting when standing, was even more skewed, affecting roughly a third of the migraine group versus about one in eight controls.¹

A case-control study among Lebanese patients found that people with migraine had roughly threefold higher odds of experiencing vasovagal syncope, the most common type of fainting, compared with controls.² These are not trivial numbers. If you have migraine and you sometimes feel faint or have actually passed out, the two are likely connected rather than coincidental.

Why the Two Conditions Share a Nervous-System Link

The dominant explanation is shared autonomic dysfunction. The autonomic nervous system controls involuntary processes like heart rate, blood-vessel tone, and blood-pressure regulation. In vasovagal syncope, an abnormal reflex causes blood vessels to dilate and the heart to slow down, starving the brain of blood and triggering a blackout. In migraine, abnormal autonomic signaling contributes to the cascade of vascular changes and pain that define an attack. The overlap is not a coincidence: both conditions involve imbalances between the sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) branches of the autonomic nervous system, with exaggerated vagal tone playing a central role.²

Research in families has noted that vasovagal syncope and migraine cluster together at higher-than-expected rates, and the lack of a strong gender skew in these family clusters has led some researchers to suggest a possible shared genetic basis with an autosomal dominant inheritance pattern.³ In plain terms, the same wiring problem that makes your brain vulnerable to migraine attacks may make your cardiovascular reflexes prone to misfiring.

There is also evidence that the brain’s ability to regulate its own blood supply is less robust in people with migraine. A study measuring cerebral autoregulation found that, compared with controls, people with migraine with aura had impaired autoregulation in both the posterior cerebellar and middle cerebral arteries. People with migraine without aura did not show the same impairment.⁴ When the brain is less able to buffer against swings in blood pressure, a momentary dip that a healthy person would barely notice can produce dizziness or a full blackout in someone with migraine.

Migraine With Aura Carries Higher Risk

Not all migraine subtypes carry the same fainting risk. Several studies converge on migraine with aura as a particularly strong predictor of syncope. In a study examining risk factors among migraine patients, having aura roughly doubled the odds of syncope compared to migraine without aura, after adjusting for other variables. The same analysis also identified being underweight and having diabetes as independent risk factors for syncope in migraineurs.⁵ A large Saudi epidemiological survey similarly found a significant association between migraine with aura and syncope.⁶

The impaired cerebral autoregulation findings described above also point in this direction: the autoregulatory deficit was specific to migraine with aura, not migraine without aura. One interpretation is that the cortical spreading depression underlying aura generates additional autonomic instability, making the cardiovascular reflexes more likely to misfire during or around an attack. If you have migraine with aura and experience faintness, this specific pattern is worth mentioning to your doctor, since it may influence both your workup and your treatment options.

Brainstem Aura and Losing Consciousness

A rarer and more dramatic overlap occurs in migraine with brainstem aura, formerly called basilar migraine. This subtype involves aura symptoms originating from the brainstem or both sides of the brain at once, and it can produce frank disturbances of consciousness that go beyond simple fainting. Case reviews describe patients experiencing drowsiness, stupor, and even coma during attacks, with the decreased consciousness lasting anywhere from seconds to hours and, in rare cases, up to two weeks. Most patients regain awareness within about half an hour.⁷

This is not the same mechanism as vasovagal syncope. In brainstem aura, the loss of consciousness is driven by the migraine event itself affecting the reticular activating system, the brainstem region responsible for maintaining wakefulness. It tends to look clinically different from a typical faint: the episodes can last much longer, the patient may cycle through varying levels of consciousness, and recovery is sometimes gradual rather than the snap-back that follows an ordinary syncopal episode. If someone with migraine loses consciousness for more than a few moments or shows fluctuating awareness, brainstem aura should be on the differential rather than assuming it was just a faint.

When Standing Up Is the Problem

For many people with migraine, the trouble is not so much full-blown fainting as a chronic intolerance of being upright. Orthostatic intolerance encompasses a spectrum of symptoms triggered by standing, including lightheadedness, blurred vision, nausea, fatigue, difficulty concentrating, palpitations, and in some cases, outright syncope.⁸ It was nearly three times more common in migraineurs than controls in the CAMERA study, and follow-up analysis found that syncope and orthostatic intolerance in migraineurs were associated with a higher burden of brain lesions on imaging.⁹

One formal expression of this overlap is postural orthostatic tachycardia syndrome, or POTS, a condition in which the heart rate spikes excessively upon standing. Migraine is the most common comorbidity in POTS patients.¹⁰ The combination creates a vicious cycle: standing provokes a surge in sympathetic activity that can trigger both a headache and presyncope (feeling like you are about to faint), and the migraine attack itself may further destabilize autonomic regulation, worsening orthostatic symptoms. People with both conditions often describe “coat-hanger pain” across the neck and shoulders when upright, brain fog, and exercise intolerance, on top of their migraine attacks.

In children and adolescents, the overlap between headache and orthostatic intolerance is common enough that pediatric headache specialists are encouraged to screen for it. Migraineurs in this age group are at increased risk of orthostatic symptoms including lightheadedness, fatigue, abdominal pain, and syncope upon standing.¹¹ Because adolescents are already prone to blood-pressure swings from rapid growth, dehydration, and irregular sleep, the addition of migraine-related autonomic instability can push them past the threshold for fainting more easily than adults.

Falls and Physical Safety

Fainting is not the only way migraine-related dizziness translates to physical harm. A study comparing migraine patients with controls found that falls and self-reported balance impairment were dramatically more common in the migraine group: about 54% reported falls and 69% reported impaired balance, compared with just 2% for each in controls. People with migraine with aura and those with chronic migraine reported the highest number of falls per year, and concern about falling during daily activities was substantially elevated across the migraine population.¹²

The fear-of-falling findings are worth taking seriously. When people begin avoiding activities because they are worried about losing their balance, deconditioning follows, which paradoxically worsens orthostatic intolerance and makes both migraines and fainting more likely. If you have migraine and are finding yourself avoiding stairs, exercise, or crowded places because of dizziness, that is a signal to discuss the problem with your doctor rather than simply restricting your life around it.

Syncopal Migraine as a Distinct Pattern

Some researchers have gone beyond documenting the overlap and proposed that a subset of patients have a condition best described as “syncopal migraine,” where fainting is essentially a manifestation of the migraine process itself rather than a separate coincidental disorder. In one clinical investigation of recurrent syncope patients, nearly a third met criteria for syncopal migraine. This group resembled the migraine population more than the syncope population in terms of demographics, autonomic testing, and associated conditions. They also had longer syncopal episodes and longer recovery times than typical fainters. Perhaps most telling, anti-migraine medications reduced the frequency of syncope in about half of these patients.¹³

The concept remains somewhat controversial. Syncopal migraine is not currently a formal diagnostic category in the International Classification of Headache Disorders, and some neurologists argue that the overlap is better explained by two common conditions sharing a vulnerability rather than by migraine directly causing fainting. Still, the finding that migraine preventive drugs can reduce syncope in this subgroup is clinically useful, regardless of the taxonomic debate.

Cardiac Concerns Worth Knowing About

Most migraine-related fainting is benign in the sense that the heart itself is structurally normal. But a conversation about migraine and syncope would be incomplete without noting the cardiovascular associations that sometimes demand investigation. Migraine with aura has been linked to a higher risk of cardiac arrhythmias, most prominently atrial fibrillation, and has been incorporated into cardiovascular risk prediction tools in some countries.¹⁴

This does not mean that every migraine patient who faints needs an extensive cardiac workup. The vast majority will have vasovagal or autonomically mediated syncope that does not indicate heart disease. But if your fainting episodes are very sudden without warning symptoms, happen during exertion, are accompanied by chest pain or palpitations, or begin later in life after years of migraine without fainting, a cardiac evaluation is reasonable. The line your doctor is trying to walk is distinguishing the common and benign (vagally mediated faint triggered by standing too long, a hot room, or a migraine attack) from the rare and dangerous (an arrhythmia that happens to coexist with migraine).

Genetic Underpinnings

A genome-wide association study looked specifically at the genetics of syncope in migraine patients and found distinct genetic variants associated with fainting susceptibility. One variant, located in an intronic region of a gene called LOC102724945, was significantly more common in migraine patients who experienced syncope than in migraine patients who did not. Crucially, the genetic variants associated with syncope in migraine patients were different from the variants associated with syncope in non-migraine controls, suggesting that the mechanism linking the two conditions in migraineurs is not simply “being prone to fainting in general” but rather a migraine-specific pathway.¹⁵

This work is early-stage. A single genetic association study does not prove causation, and the identified variants still need functional validation to understand what they actually do. But the finding fits with the broader picture: migraine and syncope are not just two common things that overlap by chance. There appears to be specific shared biology, possibly involving ion channels or vascular regulation genes, that predisposes certain brains to both conditions.

What Helps

Treatment for migraine-related syncope works best when it targets the shared autonomic problem rather than addressing each condition separately. For the majority of people, non-drug strategies make a meaningful difference. Increasing fluid intake, adding dietary salt, wearing compression garments, and following a regular exercise program all improve blood-volume regulation and make the autonomic reflexes less likely to misfire.¹⁶ These same measures often improve migraine frequency as well, since dehydration and deconditioning are known migraine triggers.

When lifestyle changes are not enough, medications can help. As the syncopal migraine research showed, migraine-preventive drugs reduced fainting in about half of patients whose syncope had a migrainous pattern. For people with both POTS and migraine, treatments that address the shared autonomic mechanisms may provide dual benefit.¹⁰ Beta-blockers, for example, are used for both migraine prevention and heart-rate control in POTS, though they need to be chosen carefully since some can worsen orthostatic hypotension.

Counter-pressure maneuvers are an underused practical tool. If you feel a faint coming on, crossing your legs and tensing the muscles, squatting, or gripping and tensing both hands can raise blood pressure enough to abort the episode. Learning to recognize your personal warning signs, whether that is a sudden wave of warmth, tunnel vision, or nausea, gives you a window to act. For people whose migraines reliably trigger presyncope, sitting or lying down at the first sign of aura may prevent a fall even if the faint itself is not fully avoidable.

The Sex Difference

Women are overrepresented on both sides of this overlap. Migraine is already about three times more common in women, and the Lebanese case-control study found that being female carried roughly ninefold higher odds of vasovagal syncope in their adjusted model.² Hormonal fluctuations likely play a role: estrogen influences vascular reactivity and autonomic tone, and many women report that both their migraines and their tendency to feel faint shift across the menstrual cycle, pregnancy, and menopause. This is an area where the evidence is stronger on the observational side than on the mechanistic side, but the clinical pattern is consistent enough that clinicians who treat migraine in women often ask specifically about orthostatic symptoms and fainting as part of the routine history.