She asked for marshmallows at the produce counter. She meant mushrooms.
Migraine brain fog between attacks is real, it has names, and it has timelines. Here is what the sources say, and where they disagree.
- Migraine brain fog between attacks is real, and the American Migraine Foundation lists trouble finding words as one of its signs
- It can start before the headache and linger after it, from a few hours up to about two days
- In a diary study, 93% of attacks ended with people back to normal within 24 hours
- The American Migraine Foundation says migraine does not make you lose your memory or lower your thinking skills
A woman once described it in a migraine forum.
She was at the grocery counter, the day after a bad attack. She asked the man behind it for marshmallows. She meant mushrooms. He stared. She felt her face and wondered if it was drooping.
Her husband stepped in. “She gets bad migraines and swaps words,” he said.
That was the whole explanation. The man nodded and went to get the mushrooms.
If you have stood at a counter with the right word just out of reach, you know the feeling underneath. It is not the headache. It is the sense that your own mind has stepped out of the room.
What is migraine brain fog between attacks?
Migraine brain fog is a set of thinking problems that travel with the attack, not only with the pain. The American Migraine Foundation lists trouble focusing and finding words, distraction, forgetfulness and trouble finishing simple tasks as signs of it.
It also says brain fog can show up on days when you have no headache at all. That is the part most people were never told.
So the fog you feel on a “good” day may not be a separate problem. It can belong to the same attack.
Does the fog come before the headache?
It can. The first phase of an attack, the prodrome, can begin several hours or days before the headache. Difficulty focusing sits on that phase’s list, next to mood changes and tiredness.
The American Migraine Foundation’s brain fog page puts a number on it. It says the fog can start up to 48 hours before the headache and last up to 24 hours after it.
You may have been calling Tuesday’s foggy afternoon a bad week. Thursday’s migraine may have already been on its way.
The day after: the migraine hangover
The last phase is the postdrome, also called the migraine hangover. Cleveland Clinic lists difficulty concentrating and mental fog among its symptoms. It says the hangover can last a few hours up to two days.
The American Migraine Foundation says the postdrome affects about 80% of people with migraine. Cleveland Clinic says more than 80%.
Brain fog the day after a migraine is common, and so is difficulty concentrating after a migraine: the diary study below found it in more than half of attacks. So the slow, strange day after an attack is common. It is not a character flaw.
How long does migraine brain fog last?
The honest answer is that sources give different ranges.
- **Cleveland Clinic:** the postdrome can last up to 48 hours.
- **American Migraine Foundation:** brain fog up to 48 hours before the headache and up to 24 hours after.
- **A diary study published in Neurology in 2016:** people were back to normal within 6 hours in 54% of attacks, and within 24 hours in 93%. In the same study, difficulty concentrating showed up in 56% of the postdromes.
These numbers do not contradict each other as much as they seem to. One counts the clock from the headache’s end, another from the first sign. Your own number is the one that matters, and a log will show it.
Can’t find words after a migraine?
It is a recognized part of brain fog. The American Migraine Foundation lists trouble finding words, and says it is temporary.
One thing we looked for and did not find: a source that measured word-finding trouble in the days between attacks, apart from the attack itself. If someone tells you exactly how common it is, ask for the study.
If you ever have new speech or language trouble, or it is different from your usual pattern, treat it as something to ask a doctor about promptly. Do not wait to see if it passes.
Is migraine brain fog permanent?
This is the question under all the others.
The American Migraine Foundation is plain about it. Migraine does not make you lose your memory, as in dementia, or lower your thinking skills.
Researchers are more careful about the days between attacks. A 2024 review in the Journal of Headache and Pain found a lack of certainty about whether thinking problems extend between attacks in episodic migraine. It says effects may be more lasting in chronic migraine, and that this is not firmly established.
Put those two together and they answer different questions. One is about long-term decline. The other is about how you function between attacks. The first has a reassuring answer. The second is still being worked out.
A migraine brain fog log
You cannot manage a fog you cannot see. So make it visible.
For a few attacks, write down three times: the first moment you felt foggy, the time the headache started, and the time you felt like yourself again. Add one line about what the fog did, whether it was missing words, losing your place or reading the same sentence twice. This is our suggestion, not medical advice.
The gap between the first and last time is your own migraine hangover, in your own handwriting. It is also the thing to bring to your doctor, because it tells them where the attack really begins and ends.
Questions
What is migraine brain fog between attacks?
It is trouble focusing, finding words, remembering and finishing simple tasks that comes with a migraine attack. The American Migraine Foundation says it can happen on days without a headache.
Why do I have brain fog after a migraine?
The last phase of an attack, the postdrome, can bring mental fog and difficulty concentrating. Cleveland Clinic says it can last a few hours up to two days.
How long does migraine brain fog last?
Sources differ. Cleveland Clinic says up to 48 hours. The American Migraine Foundation says up to 48 hours before the headache and up to 24 hours after. In a 2016 diary study, 93% of attacks ended with people back to normal within 24 hours.
Can’t find words after a migraine: is that normal?
The American Migraine Foundation lists trouble finding words as part of migraine brain fog and describes it as temporary. New or unusual speech trouble is worth raising with a doctor promptly.
Is migraine brain fog permanent?
The American Migraine Foundation says migraine does not make you lose your memory or lower your thinking skills. A 2024 review says it is still uncertain whether thinking problems extend between attacks in episodic migraine.
Can brain fog come before the headache?
Yes. Difficulty focusing is listed in the first phase, the prodrome, which can begin several hours or days before the headache.
Where the line comes in
If the fog can start before the pain and linger after it, the real question is how close your brain was to the edge when the week began.
There is a name for that edge. The Migraine Tipping Line™.
Read what the Migraine Tipping Line™ is, and why your diary never found it →Part 2What the research says
Trouble focusing and finding words, distraction and forgetfulness are listed signs of migraine brain fog.
The fog can happen on days without a headache.
Read the sourceMental fog and difficulty concentrating are listed postdrome symptoms.
The postdrome can last a few hours up to 48 hours.
Read the sourcePeople were back to normal within 6 hours in 54% of attacks and within 24 hours in 93%.
Difficulty concentrating was reported in 56% of postdromes.
Read the sourceIt is uncertain whether thinking problems extend between attacks in episodic migraine.
Effects may be more lasting in chronic migraine, but this is not firmly established.
Read the sourceA migraine attack has four phases, and the first can begin several hours or days before the headache.
Difficulty focusing is on the prodrome list.
Read the sourceThe 2016 diary study and the 2024 review report different things, so we cite each for its own finding.
Your turn
What does your fog do first: the missing word, the lost place, or the reread sentence?
Tell us below. Someone reading along may see their own foggy day in your answer.
Tell us what your fog does firstWe read every comment. Comments are reviewed before they appear, so please do not share personal medical details.
Content on this site is educational and is not medical advice.