Symptoms

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 for anywhere between an hour to 10 days
• Can occur anywhere in the head or neck
• Can be accompanied by nausea or vomiting

When to see a doctor
Seek immediate medical attention for any headache that comes on suddenly and severely.

Causes

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
• 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
• Death of tissue or bleeding in the pituitary gland
• A blood clot in the brain
• Severe elevation in blood pressure
• Infection such as meningitis or encephalitis

Preparing for your appointment

Thunderclap headaches are often first diagnosed by an emergency room physician. However, in some cases when you call to set up an appointment, you may be referred immediately to a doctor who specializes in the brain and nervous system (neurologist).

If you have time before your appointment, it's a good idea to be well prepared. Here's some information to help you get ready for your appointment, and to know what to expect from your doctor.

What you can do

• Write down any symptoms you're experiencing, including any that may seem unrelated to your headaches.
• Write down key personal information, including any major stresses or recent life changes.
• Make a list of all medications, vitamins and supplements you're taking.
• Take a family member or friend along, if possible. Sometimes it can be difficult to take in all the information you get during an appointment. Someone who accompanies you may remember something you missed or forgot.
• Write down questions to ask your doctor.

Preparing a list of questions will help you make the most of your time with your doctor. For thunderclap headaches, some basic questions to ask your doctor include:

• What is likely causing my headaches?
• Are there other possible causes for my headaches?
• What tests do I need?
• Is my condition likely temporary or chronic?
• What is the best course of action?
• What are the alternatives to the primary approach you're suggesting?
• I have these other health conditions. How can I best manage them together?
• Are there any restrictions I need to follow?
• Should I see a specialist?
• Is there a generic alternative to the medicine you're prescribing?
• Are there brochures or other printed material I can take with me? What websites do you recommend?

Don't hesitate to ask questions that occur to you.

What to expect from your doctor
Your doctor is likely to ask you a number of questions, including:

• When was your first thunderclap headache?
• Have your headaches been continuous or occasional?
• How severe are your headaches?
• What, if anything, seems to improve your headaches?
• What, if anything, appears to worsen your headaches?

Tests and diagnosis

The following tests are commonly used to determine if any underlying condition is causing thunderclap headaches.

CT scan
Testing often starts with a computerized tomography (CT) scan of the head to search for an underlying cause of the headache. CT scans take X-rays that create slice-like, cross-sectional images of your brain and head. A computer combines these images to create a full picture of your brain. Sometimes an iodine-based dye is used to augment the picture.

Spinal tap
Sometimes a spinal tap (lumbar puncture) may be needed as well. With this procedure, the doctor removes a small amount of the fluid that surrounds your brain and spinal cord. The cerebrospinal fluid sample can be tested for signs of bleeding or infection.

MRI
In some cases, magnetic resonance imaging (MRI) may be done for further assessment. With this imaging study, a magnetic field and radio waves are used to create cross-sectional images of the structures within your brain.

Magnetic resonance angiography
MRI machines can also be used to map the blood flow inside your brain in a test called a magnetic resonance angiography (MRA).

Treatment and drugs

There's no single treatment for thunderclap headaches because so many potential causes exist. Treatment is aimed at the underlying cause of the headaches — if one is found.

Coping and support

You may find it useful to talk to other people who experience painful headaches. Try finding a support group in your area to learn how other people cope with their headache pain and discomfort.