All you need to know about thunderclap headaches

Thunderclap headaches feel like a sudden, tight clamp or band of pain around the head.
Thunderclap headaches may be a symptom of an underlying condition.
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What you need to know:

  • Thunderclap headaches are sudden, intense events that go as quickly as they came.
  • It is important to get a diagnosis to rule out any underlying causes.
  • Lifestyle changes, such as reducing stress and managing high blood pressure, may help.

The word 'thunderclap' describes this type of headache's sudden, severe nature.

Patients experience this headache as if a clamp is squeezing their head. They usually come on without warning and reach their maximum intensity within 60 seconds.

Thunderclap headaches can be so severe that they disrupt daily activities or result in a loss of consciousness.

They are often described as "the worst headache of my life." In some cases, they may be accompanied by numbness, nausea, vomiting, and neurological symptoms such as visual changes, confusion, and seizures.

Thunderclap headaches could signify a severe condition or, in some cases, could be benign.

Overall, one needs to be aware of the possibility and get to a hospital for further evaluation if this type of headache is experienced.


Thunderclap headaches are usually grouped in secondary headaches, meaning another underlying condition causes them. It is not clear yet what exactly causes them. However, the most probable cause of thunderclap headaches is a ruptured aneurysm. Other causes include:

  • Subarachnoid haemorrhage (bleeding in the space around the brain)
  • Reversible cerebral vasoconstriction syndrome (a condition that narrows the blood vessels in the brain)
  • Ischemic stroke
  • Primary angiitis of the central nervous system (inflammation of the blood vessels in the brain)
  • Cerebral venous sinus thrombosis (a blood clot in a vein in the brain)
  • Infections such as meningitis
  • Bleeding in the pituitary glands
  • During pregnancy, thunderclap headaches may be a sign of pregnancy complications.

In rare cases, this headache is concluded as a primary headache, meaning that the thunderclap headache is the diagnosis. However, this is only after all other possible causes have been ruled out.

Diagnosing thunderclap headaches

Thunderclap headaches require immediate medical attention. If you experience a thunderclap headache, go to the nearest medical facility.

Diagnosing thunderclap headaches requires a careful medical history and physical examination. First, your doctor will ask about your symptoms and when they started. They'll also ask about your medical history, including any previous headaches. Finally, your doctor may order tests to rule out other causes of your symptoms.

One recommended test is an MRI which can provide information about the brain and spine. Other tests may include:

  • Lumbar puncture (spinal tap) to collect cerebrospinal fluid for analysis
  • MRA or CTA scan to check the brain for aneurysms or other problems with the blood vessels

Treating thunderclap headaches

Treatment for thunderclap headaches usually involves taking medications to relieve pain and inflammation. For example, non-steroidal anti-inflammatory medicine may be used.

However, additional treatment may be necessary in some cases, such as when an underlying medical condition causes headache.

For example, if thunderclap headaches are caused by a blood clot, you may need to take blood thinners or have surgery to remove the clot.

In most cases, however, thunderclap headache treatment is fairly straightforward and can effectively relieve symptoms. Talk to your doctor about the best treatment options if you suffer from thunderclap headaches.


There is no known way to prevent thunderclap headaches. However, managing any underlying medical conditions can lower your risk of developing a thunderclap headache. For example, if you have blood pressure, work with your doctor to keep it under control. Likewise, if you have an aneurysm, follow your doctor's recommendations for monitoring and treatment.

Differences between thunderclap headaches and migraine headaches

Although thunderclap headaches can be severe, they are not the same as migraines. Migraine headaches are a primary headache disorder that causes recurrent attacks of moderate to severe pain. Thunderclap headaches are usually secondary headache disorders that occur due to another underlying condition.

Thunderclap headaches tend to come on suddenly and reach their maximum intensity within 60 seconds. Migraine headaches usually come on gradually and can last for hours or even days. Thunderclap headaches are typically one-time events. Migraine headaches tend to recur.


Lifestyle changes, such as managing underlying medical conditions and reducing stress, may help prevent thunderclap headaches. Patients with high blood pressure are at a higher chance of experiencing thunderclap headaches. Therefore, they should work with their doctor to keep it under control.

If you experience a thunderclap headache, seek medical attention immediately. Early diagnosis and treatment of the underlying condition are essential to preventing serious complications.