How to Spot a Migraine Coming On: Prodrome Symptoms Explained

Most migraine attacks do not start when the pain starts. They start earlier, sometimes hours earlier, sometimes a day or two earlier, in a quiet phase called the prodrome. If you have ever said "I felt weird all afternoon and then it hit me at bedtime", you were describing your prodrome. Learning to read it is one of the highest-leverage skills in living with migraine.

The short answer

The prodrome is the early-warning phase of a migraine attack. It can begin anywhere from a couple of hours to about 48 hours before the headache and shows up as a mix of mood, appetite, energy, cognitive and body-sensation changes. It is easy to miss because none of the symptoms are dramatic on their own. What matters is the combination and the fact that they cluster before an attack. Spotting your personal prodrome pattern gives you a window to hydrate, rest, dim the environment, take medication early if your doctor has advised it, and lower the odds that a bad day turns into a wasted day.

What actually is the prodrome

Migraine is a four-phase event: prodrome, aura (only about a third of people get this), headache, and postdrome. The prodrome reflects changes in the hypothalamus and brainstem before the pain pathways switch on. That is why the earliest symptoms are so oddly assorted. The hypothalamus regulates appetite, sleep, thirst, mood and autonomic tone, so when it starts misbehaving, all of those can wobble at once.

Research using headache diaries suggests that more than 75 percent of people with migraine experience at least one prodrome symptom, and many experience several. Some people are consistent (the same signals every time) and some are variable. Both patterns are normal.

The most common prodrome symptoms

You will not get all of these in one attack. Most people notice two or three that repeat.

• Yawning. Repeated, unexplained yawning is one of the most reliable prodrome signals. If you find yourself yawning through a meeting you are not bored by, take note.
• Fatigue and low energy. A heavy, flat feeling that does not match how much sleep you had.
• Mood changes. Irritability, low mood, anxiety, or occasionally a strange euphoria. Family members often spot this before you do.
• Food cravings. Classically chocolate, sweet or salty foods. This is a symptom of the migraine starting, not the cause of it.
• Neck stiffness or ache. A tight, sore neck the day before an attack is extremely common and often gets mistaken for posture or stress.
• Difficulty concentrating. Words feel slippery, you re-read the same paragraph, small tasks feel effortful.
• Increased sensitivity to light, sound or smell. The world feels louder or brighter than usual.
• Frequent urination or increased thirst. A hypothalamic signal, not just something you did to yourself.
• Digestive changes. Nausea, bloating, constipation or, less often, loose stools.
• Cold hands, pale skin, or shivering. Autonomic changes as the attack builds.

Prodrome, aura and the headache: how to tell them apart

These get muddled, so it is worth separating them.

• Prodrome is slow and vague. Hours to days. Mood, energy, appetite, neck. No sharp neurological symptoms.
• Aura is fast and neurological. Usually 5 to 60 minutes. Visual zig-zags, blind spots, pins and needles, speech disturbance. Only about a third of people with migraine get aura.
• The headache phase is the pain itself, often throbbing, often one-sided, usually with nausea or light and sound sensitivity.

If a symptom lasts hours and is not visual or sensory, it is almost certainly prodrome, not aura.

Why the prodrome matters

The prodrome is a window of opportunity. Once the headache phase is fully underway, medications work less well and behavioural strategies help less. In the prodrome you can still influence the outcome. Common sensible steps, ideally agreed with your clinician in advance, include:

• Hydrate deliberately and eat something with slow carbohydrate and some salt.
• Reduce sensory load. Dim screens, cut background noise, get outside for gentler daylight rather than staring at a bright monitor.
• Move gently. A short walk can settle autonomic symptoms. Intense exercise usually cannot.
• Sleep-protect the next 12 hours. Prioritise a proper bedtime and avoid alcohol.
• Talk to your GP or neurologist about early-treatment plans. Some people are advised to take a triptan or NSAID at prodrome onset, some are not. This is a medical decision, not a self-help tip.

How to tell your prodrome from a normal off-day

Everyone has flat, foggy, snacky days that do not turn into migraines. The trick is not to react to every single one of them. Two things separate a real prodrome from noise:

• The cluster. One symptom on its own is weak evidence. Three or four at the same time is much stronger. Yawning plus neck ache plus a craving plus concentration wobble at 4pm is a different signal from feeling tired at 4pm.
• The pattern over time. A symptom that repeatedly shows up in the 24 hours before your attacks is a personal prodrome signal. A symptom that appears on plenty of headache-free days too, is not. You cannot tell the difference from memory alone. You need a diary and enough attacks logged to compare.

How MigraineMe helps with this

MigraineMe runs a dedicated prodrome worker on the server. Each day it reads the health metrics coming in from your wearable, phone and health app, and fires an early-warning event into a table called prodromes whenever a value crosses an absolute threshold or sits more than two standard deviations from your own fourteen-day baseline for that metric. These events are tagged as auto-captured (source "system"), so you can see they came from your data rather than something you logged by hand.

The prodrome worker does not diagnose you and it does not read subjective symptoms like yawning or cravings, which only you can notice. What it can do is flag the physiological shifts that often accompany a prodrome (for example an unusual sleep night, a recovery score well below your baseline, a stress-index reading outside your normal range) so you have an objective record to sit alongside the way you feel.

Those prodrome events then feed the daily risk score. The risk score worker takes every fired trigger and prodrome event, applies a per-severity decay weight so recent signals count for more than older ones, and produces a daily score, a percent, and a zone (NONE, LOW, MILD or HIGH). The current risk gauge is free. If you upgrade to Premium, you also see the 7-day forecast: the same calculation projected out for the next seven days, so you can look ahead when several signals are stacking up.

Over time, once you have logged at least three migraines and have at least three headache-free control days, the server-side insights engine (compute-correlation-stats) starts telling you which factors are actually associated with your attacks. It uses Fisher's exact test for significance and a lift ratio with Haldane-Anscombe smoothing for effect size, checks lags of 0 to 3 days, and applies both Bonferroni and Benjamini-Hochberg corrections so sparse data does not produce false positives. A three-dot meter shows how strong the p-value is. There are no confidence intervals and MigraineMe does not claim any.

None of this is a medical device and none of it replaces your clinician. It is a way to build up an honest, personal picture of what happens in the hours and days before an attack, so "I felt weird all afternoon" can become "my sleep score was low, my recovery was flagged, my risk went into MILD, and I got the neck ache I always get". That is a much better conversation to bring to a neurologist.