Thunderclap Headaches

Medically Reviewed by Carmelita Swiner, MD on November 10, 2022
3 min read

This rare type of severe headache comes on suddenly. It can cause intense pain and often nausea and vomiting. If you have one, get emergency medical attention. The cause, which can be life-threatening, is often some kind of bleeding in or around your brain.

People often call this the first worst headache of their life. It comes out of nowhere. The pain peaks within a minute, lasts about 5 minutes, and then goes away. Take a sudden new headache seriously. It’s often the only warning you get of a serious problem.

Unlike a migraine, thunderclap headaches seem to come on suddenly. The pain grabs your attention in the same way a clap of thunder does. You can feel pain anywhere on your head or neck. You may even feel it in your back.

You might also have several other symptoms, including:


Thunderclap headaches could be caused by bleeding from an artery into the space surrounding your brain. This is known as a subarachnoid hemorrhage. Arteries are vessels that supply blood to your brain.

A thunderclap headache could also be caused by any of the following:

  • Small tears in the arteries of your head or neck
  • A burst artery or aneurysm, which is a swollen, weak area in the artery
  • Blocked veins in your head
  • Leaking spinal fluid
  • Rapid changes in blood pressure
  • An infection in your brain
  • Head injury
  • Hemorrhagic stroke (This comes from a ruptured blood vessel in your brain.)
  • Ischemic stroke (This comes from a blocked blood vessel, due to a blood clot, or plaque.)
  • Narrowed blood vessels surrounding the brain
  • Inflamed blood vessels
  • Extremely high blood pressure in late pregnancy

Some activities such as the following could trigger a thunderclap headache:

  • Hard physical labor
  • Taking certain drugs, including illegal ones
  • Hitting warm or hot water too fast, such as when you first enter a shower or bath


Your doctor will probably ask you questions, like:

  • Have you had other headaches like this?
  • Have you had other types of headaches before?
  • If so, were they continuous or occasional?
  • Describe the headaches and their symptoms
  • How severe were your headaches?
  • Does anything make them better?
  • Does anything make them worse?

Your doctor will also use tests like:

  • CT scan of the head. This imaging test takes X-rays that create slice-like, cross-sectional images of your brain and head. A computer combines them to create a full picture of your brain. The doctor might inject an iodine-based dye into your veins to make parts of your brain stand out.
  • Spinal tap (lumbar puncture). If you need this test, the doctor will take out a small amount of the fluid that surrounds your brain and spinal cord. They can test it for signs of bleeding or infection.
  • MRI. This imaging test is often used as a follow-up to a CT scan. It uses a magnetic field and radio waves to create cross-sectional images of the inside of your brain.
  • Magnetic resonance angiography. MRI machines can be used to map the blood flow inside your brain in a test called a magnetic resonance angiography (MRA).


Thunderclap headache treatment depends on what’s causing the pain.