What is Thunderclap Headache?

Thunderclap headache is a sudden, severe headaches peaks within 60 seconds and can start fading after an hour. Some thunderclap headaches, however, can last for more than a week. Thunderclap headaches are often a warning sign of potentially life-threatening conditions, usually linked to bleeding in and around the brain. That's why it's so important to seek emergency medical attention if you experience a thunderclap headache.

Some people may also experience thunderclap headaches as part of a potentially recurring headache disorder, known as primary thunderclap headache. But this diagnosis should only be made after a thorough medical evaluation and elimination of other possible underlying causes.

Thunderclap headaches are dramatic. Symptoms include pain that:

Strikes suddenly and severely — sometimes described as the worst headache ever experienced
Peaks within 60 seconds
Lasts anywhere between an hour and 10 days
Can occur anywhere in the head, and may involve the neck or lower back
Can be accompanied by nausea, vomiting or loss of consciousness

Some thunderclap headaches appear as a result of no obvious physical reason.In other cases, potentially life-threatening conditions may be responsible, including:

Bleeding between the brain and membranes covering the brain, often due to an abnormal bulge or ballooning in a blood vessel (aneurysm)
A rupture of a blood vessel in the brain
A tear in the lining of an artery (for example, carotid or vertebral artery) that supplies blood to the brain
Leaking of cerebrospinal fluid, which when present is usually due to a tear of the covering around a nerve root in the spine
A tumor in the third ventricle of the brain that blocks the flow of cerebrospinal fluid
Loss of blood supply to or bleeding in the pituitary gland
A blood clot in the brain
Severe elevation in blood pressure
Infection such as meningitis or encephalitis