Thunderclap headaches are severe headaches that develop rapidly. They can be a sign of a serious underlying medical condition, such as stroke. As such, they require immediate medical attention.

This article discusses the symptoms of thunderclap headaches, as well as their potential causes and treatment options.

What is a thunderclap headache?

Fever and weakness may accompany a thunderclap headache.
A thunderclap headache is a severe headache with a rapid onset. While other types of headache build up slowly, thunderclap headaches tend to peak within 60 seconds. They typically occur without an obvious trigger.

In some cases, a thunderclap headache may indicate a serious underlying medical condition that requires urgent treatment. As such, anyone who experiences this type of headache should seek immediate medical attention.

Symptoms
The primary symptom of a thunderclap headache is severe head pain. The pain reaches full intensity within a minute and lasts at least 5 minutes.

Other symptoms that may accompany a thunderclap headache include:

• fever
• weakness
• loss of vision
• nausea and vomiting
• pain in the neck or back
• confusion
• difficulty thinking and speaking
• The exact symptoms a person experiences will depend on the cause of the headache.

Causes
It is not always clear what causes a thunderclap headache. In some cases, a recurring headache disorder might be responsible. However, it can also be the result of something more serious, such as damage to structures within the brain.

The most common serious cause of a thunderclap headache is a subarachnoid hemorrhage, but these headaches can occur without a serious cause. A subarachnoid hemorrhage is a rare type of stroke caused by bleeding deep in the brain. Subarachnoid hemorrhages are very serious and require immediate medical care.

Other possible causes of a thunderclap headache include:

ischemic stroke, resulting from a blocked artery within the brain
an enlarged artery, or aneurysm, in the brain
infections of the brain, such as bacterial or viral meningitis
head trauma
Treatment
The treatment for a thunderclap headache depends on its cause. If a person experiences a thunderclap headache without a known cause, they must seek immediate medical treatment.

If the person knows the cause, and it is not serious, it may be possible to treat the pain at home using over-the-counter painkillers or with prescription medication that a doctor has prescribed for headaches.

We outline some potential causes and complications of thunderclap headache and their associated treatments below.

Stroke
If a thunderclap headache is the result of an ischemic stroke, doctors will treat it with medications to try to prevent brain damage. In some situations, this may involve medications to break up the clot that is causing the stroke. Doctors may administer these drugs intravenously via a drip or with an interventional procedure.

If a thunderclap headache occurs due to hemorrhagic stroke, doctors will work to minimize brain damage and slow or stop the bleeding. This may involve surgery to secure a blood vessel and prevent further bleeding.

In the case of hemorrhagic stroke, it will also be necessary to identify and treat the cause of the bleed. According to the American Heart Association, the most common trigger is high blood pressure. In such cases, doctors may prescribe blood pressure-lowering medications, or antihypertensives to reduce the risk of another bleed.

Brain infections
Meningitis is an infection that causes inflammation of the lining of the brain and spinal cord. There are two types: viral and bacterial, with viral being the most common.

According to the Centers for Disease Control and Prevention (CDC), there is generally no curative treatment for viral meningitis (VM). However, people who develop VM as a result of herpesvirus or influenza may benefit from antiviral medications.

Bacterial meningitis requires immediate treatment with antibiotics. Without such treatment, the infection can progress, causing brain damage, and it may potentially be fatal.

Brain damage
If there is lasting damage to the brain, a doctor may recommend rehabilitation through various types of therapy. Examples include speech therapy and physical therapy.

Diagnosis
Doctors often find diagnosing a thunderclap headache challenging. Although such headaches often signal a serious underlying medical condition, sometimes the cause can be relatively benign.

Some accompanying symptoms that may signal a serious underlying medical condition include:

• confusion or change in consciousness
• fever
• weakness
• visual disturbances
• difficulty thinking or speaking
• unusual sensations
• if a thunderclap headache is an early symptom of an underlying medical condition, a person may not have any other symptoms. To help with diagnosis, a doctor may use medical imaging such as a head CT scan or MRI.

Risk factors
Certain activities may trigger a thunderclap headache in some people. Examples of such activities include:

• physical activity
• sexual activity
• straining during a bowel movement
• Prevention
• Whether it is possible to reduce the risk of a thunderclap headache depends on its cause. Some general tips to reduce the risk of underlying conditions that may cause a thunderclap headache include:

• maintaining a healthful diet
• exercising regularly
• maintaining a healthy weight
• managing underlying conditions, such as heart disease and hypertension
• avoiding smoking
• moderating alcohol use
• How it differs from other types of headache
• The following types of headache can cause pain of a similar severity to thunderclap headaches. However, unlike thunderclap headaches, their causes are usually less serious.

Ice pick headaches: Headaches that involve brief stabbing pains in the front or side of the head.
Migraines: Headaches that involve a severe throbbing or pulsing ache on one side of the head. These can occur alongside other symptoms, such as nausea and vomiting.
Cluster headaches: Severe headaches that occur quickly, usually around the front of the head or face. They typically cause problems with one eye, such as watering. Like thunderclap headaches, they tend to have a rapid onset.
When to see a doctor
The presence of a thunderclap headache can indicate a severe and potentially life-threatening medical condition. Such conditions can develop within a very short timeframe. Without treatment, their effects may be serious and long-lasting.

Anyone who experiences a thunderclap headache should, therefore, seek urgent medical attention.

Outlook
The outlook for a thunderclap headache depends entirely on its cause.

In some cases, there is no apparent cause, and the headache may never happen again. In other cases, it could be the result of a recurring headache disorder.

In the most severe cases, thunderclap headaches may be due to a serious underlying medical condition, such as subarachnoid hemorrhage or a stroke. The outlook in these cases will depend on various factors, including the extent of the brain damage, and the person’s overall health.

Summary
A thunderclap headache refers to severe head pain with a rapid onset. It can be a sign of a serious underlying condition, such as a bleeding blood vessel in the brain.

Depending on the cause of a thunderclap headache, other symptoms may or may not be present. Some symptoms that signal a potentially serious cause include weakness, sensory disturbances, and confusion.

Anyone showing signs of a thunderclap headache must seek immediate medical attention. Depending on the cause, doctors may need to provide emergency treatments.

VascularHeadache / MigraineNeurology / Neuroscience