Acephalgic migraine, or "silent migraine," is a form of migraine that occurs without an actual headache.

Symptoms

There are four phases of a migraine attack. While an acephalic migraine can go through the prodrome phase (when symptoms warn of an impending attack), the aura phase (visual disturbances that precede an episode), and the postdrome (or post-headache) phase, it skips the headache phase, which is considered the hallmark symptom of all other types of migraine.

Because of this, those with silent migraine usually do not have the one-sided head pain that other migraineurs do. They also are less likely to experience symptoms like sensitivity to light, sound, and odors at the height of their episodes.

2:05 5 Types of Migraine Auras Visualized and Explained

Even if no headache is involved, silent migraines can be extremely disruptive to daily activities. The classic "half-moon" visual disturbance (where there is vision loss in half of both eyes), alterations in color perception, and other vision problems are also common.

A silent migraine can last from 15 to 30 minutes, but it is usually no longer than 60 minutes. It can recur or appear as an isolated event.﻿﻿

Causes

As with migraine disease in general, the exact causes of a silent migraine are not fully understood. Triggers for silent migraines are the same as those for other types of headaches. They can include skipped meals, skimping on sleep, specific foods or types of light, and stress, among other things.

People over 50 are more likely to have symptoms of acephalgic migraine. They can occur in those who have previously suffered full migraine symptoms or develop out of the blue.﻿﻿

When they occur in older people who have had migraines before, symptoms such as nausea, vomiting, and sensitivity to light and sound tend to diminish along with the headaches.

Acephalgic migraines account for 3% of migraines in women and 1% of migraines in men, according to a 2015 study in the Journal of Medical Case Reports.﻿﻿

Diagnosis

It can be especially tricky for a doctor to diagnose migraines when there is no headache. In some cases, people have mistakenly been diagnosed with epilepsy, based on the neurological symptoms present in the attacks. It's also possible to misdiagnose an acephalgic migraine as a transient ischemic attack (TIA) or stroke.

Specialists say acephalgic migraine should be considered as a cause whenever there is an acute episodic neurologic disorder, regardless of whether it includes headache symptoms.﻿﻿

Treatment

Treatment of silent migraines includes preventive treatments commonly used for typical migraines with headache such as medications to treat high blood pressure, antidepressants, and antiseizure medications.

Newer treatments to prevent migraines with and without auras, such as anti-CGRP (calcitonin gene-related peptide) medications, and newer devices like Cefaly (a transcutaneous electrical nerve stimulation device) have not been studied in people with acephalgic migraine but may potentially be beneficial.

A Word From Verywell

It is important to consult a physician if you repeatedly experience silent migraine symptoms. Depending on the circumstances, your doctor may want to run tests to rule out more serious conditions, such as a TIA or seizures. If you do receive a diagnosis of silent migraine, it may be helpful to examine whether any of the traditional migraine triggers bring on the symptoms.