Confusional migraine, also known as acute confusional migraine (ACM) or complex confusional migraine, is a rare type of migraine that primarily affects children and teenagers.

About 10 percent of school-aged children have migraine. Within this group, less than 8 percent are classified as ACM cases.

Researchers have noted that ACM may be underdiagnosed, so the actual number could be higher. In contrast, non-ACM migraine is common, affecting some 12 percent of people in the United States.

Although migraine has been studied for many years, ACM is still in the early stage of medical research. Only a small number of case studies can be found in medical literature.

Several researchers have recommended that ACM be added to the official International Classification of Headache Disorders as a “migraine variant.” This may help doctors more easily recognize this type of migraine.

ACM takes its name from the main symptom, which is a state of intense confusion that occurs suddenly and lasts longer than the headache.

The average episode is approximately 5 hours. Generally, an episode can be as short as 30 minutes or as long as 24 hours.

During an ACM attack, you may experience symptoms that include:

You’re alert during the episode. But as symptoms fade, you may need a period of deep sleep and recovery, and you may not remember what occurred.

You should seek immediate medical care if you’re having symptoms of an ACM attack. Your doctor will determine what exactly is causing these symptoms and whether they’re the result of ACM or another underlying condition.

Case studies from 2012 have shown that ACM can be treated with medications used for common migraine, along with other drugs. These can include:

  • over-the-counter pain relievers and nonsteroidal anti-inflammatories (NSAIDs)
  • topiramate (Topamax)
  • intravenous (IV) valproic acid
  • IV prochlorperazine
  • high-flow oxygen therapy

The average episode lasts 5 hours, but in some cases it can be less than an hour or go on for a full day.

All symptoms resolve after the episode, and you may not have any memory of the event.

Photosensitive epilepsy affects about 3 percent of people with epilepsy and is common among children. It occurs when flashing lights or certain patterns trigger seizures, which are shifts in the brain’s electrical activity.

Headaches sometimes precede seizures. The symptoms during a seizure may include uncontrollable muscle spasms, falling, and clenched teeth, as well as loss of consciousness, followed by confusion.

Most seizures last less than 2 minutes. For a seizure that lasts more than 5 minutes, get treatment immediately. By contrast, an ACM attack may last for hours.

Classic migraine attacks can sometimes be triggered by light or sound. Photosensitive epilepsy is relatively rare compared to the number of people who experience photosensitive headaches or migraine.

It isn’t clear what causes ACM, and research about what might trigger this is ongoing. More ACM cases are being studied with neuroimaging.

One possible cause is a bump on the head, which is reported in about half of ACM cases. Emotional stress and strenuous exercise have also been suggested as triggers.

In contrast, triggers for other types of migraine have been well-documented. Common migraine triggers are:

  • environmental factors, such as odors, noise, bright lights
  • food or drinks, such as salty foods or wine
  • psychological factors, such as increased stress
  • physiological factors, such as exercise that provokes migraine activity in the brain

A doctor often must first eliminate the possibility of other conditions that show similar symptoms.

Doctors may rule out epileptic seizures, stroke, and encephalitis before coming to an ACM diagnosis. Transient global amnesia syndrome must also be ruled out in adults.

According to a 2012 review of ACM, doctors should consider screening for electrolytes, glucose levels, and drugs.

If you don’t have a history of migraine, your doctor may order imaging tests, such as an MRI or CT scan of your brain. If they suspect you have an infection, they may recommend a spinal tap.

Your doctor may also use the length of your episode and the symptoms present to rule out any other conditions. It’s important that your doctor considers your personal health history and your family’s medical history.

Not much is known about risk factors for ACM. Having a family history of migraine attacks is the leading risk factor for ACM.

For classic migraine, if one or both of your parents have it, you have a 50 to 75 percent chance of also having it.

Once your symptoms are resolved, usually after a few hours, you may not remember much of the event.

You may have subsequent episodes of migraine, possibly of the non-ACM variety. Non-ACM migraine attacks have specific triggers and a known pattern of development.

A doctor may prescribe medication to help prevent future ACM or non-ACM attacks. Medication may also be used to lessen migraine severity.

Because the triggers of ACM aren’t fully known, there aren’t specific guidelines for preventing new ACM episodes.

Researchers in 2012 reported a small number of cases in which sodium valproic acid and intravenous valproic acid successfully eased an ACM episode and deterred further episodes.

Valproic acid reduces brain excitability, which is thought to be a factor in migraine susceptibility.

If you have further attacks of any non-ACM migraine, there are some things that you can do. Keeping a log or journal is a first step to help manage migraine attacks. You should keep a record of:

  • when your migraine attacks tend to occur
  • what precedes your migraine attack
  • how long the attacks last
  • what symptoms you experience
  • what helps alleviate the pain

You and your doctor can use this information to develop an individualized treatment plan.

In addition to avoiding or limiting interaction with your known triggers, you can also take pain medication as soon as you suspect a migraine is about to occur.

You may also be interested in joining a migraine support group online or in person to see how others cope with migraine.