Thunderclap headaches are sudden onset severe headache pain which may happen for no apparent reason. Their name comes from the way this headache begins — unexpectedly, intense, and strong, like a clap of thunder.

A common trigger of thunderclap headaches is a stroke or aneurysm, so it is imperative to see your doctor right away if you experience a thunderclap headache.

About 1 in 2,400 adults suffer from a thunderclap headache each year.

Let’s take a look at symptoms, causes, treatment, and prevention of thunderclap headaches.

What is a thunderclap headache?

A thunderclap headache (sometimes abbreviated as TCH) is a severe headache disorder that begins quickly and lasts for at least 5 minutes.

Thunderclap headaches are very rare. Only 43 in 100,000 adults experience a thunderclap headache within a calendar year.

Are thunderclap headaches serious? Yes, thunderclap headaches are serious, as this excruciating pain may indicate a dire problem with your circulatory system or in your brain.

Often, what causes this kind of sudden headache is unknown. However, two likely causes are blood vessel tears or issues with the brain, which is why it’s wise to seek medical help right away.

What is primary TCH? Primary thunderclap headache is when TCH occurs as its own type of headache, not a symptom of another condition. Secondary TCH is when a thunderclap headache is a result or symptom of another condition, such as a stroke.

However, some researchers claim there are no such thing as “primary thunderclap headaches”. More and more believe reversible cerebral vasoconstriction syndrome (RCVS) is the most common trigger of “primary TCH”, making so-called primary TCH just another secondary TCH.

What does a thunderclap headache feel like?

A thunderclap headache feels like a severe headache from nowhere with an overwhelming level of headache pain. It reaches its maximum intensity within 1 minute from onset.

Direct symptoms of a thunderclap headache include:

  • Sudden onset headache
  • Severe head pain

These indirect symptoms may accompany thunderclap headaches:

  • Altered mental state
  • Confusion
  • Weakness
  • Fever
  • Numbness
  • Seizures
  • Nausea and/or vomiting
  • Speech and thought difficulty

Call your doctor when… 

Thunderclap headaches can be very serious since they may indicate your blood vessels are damaged or blocked, triggering a life-threatening stroke. You should call your doctor or go to the emergency department right away if you experience this kind of pain.

Even if you’re unsure whether or not you’re experiencing a thunderclap headache, seek immediate medical attention if you…

  • Do not know the cause of your severe headache pain
  • Get confused
  • Can’t see
  • Have a fever
  • Feel weak
  • Feel numb
  • Have difficulty speaking
  • Can’t think straight

A medical professional can determine if you are suffering from a stroke or another severe condition that requires prompt treatment.

Causes & Triggers of Thunderclap Headaches

What can cause thunderclap headaches? Here are the most common triggers of thunderclap headaches:

  • Aneurysmal subarachnoid hemorrhage (also called SAH; blood leaking around the brain; complication of hemorrhagic stroke or cerebral aneurysm)
  • Reversible cerebral vasoconstriction syndrome (also known as RCVS)
  • Blood vessel problems, such as vasculitis, swelling, artery dissection, or blockage
  • Ischemic stroke (blocked blood vessel, often due to venous thrombosis AKA blood clot)
  • Hemorrhagic stroke (blood vessel bursting in brain)
  • Cerebral aneurysm (weakened blood vessel bulging and possibly rupturing)
  • Cerebral venous sinus thrombosis
  • Spontaneous intracranial hypotension (low cerebrospinal fluid)
  • Spontaneous spinal epidural hematoma (rare spinal cord compression disorder)
  • Pituitary apoplexy (during pregnancy, when the pituitary gland bleeds)
  • Sexual activity (called “post coital thunderclap headache”)
  • Intense exercise
  • Switching between multiple personalities (called “transitional interpersonality thunderclap headache”)
  • Infection in the brain, such as meningitis or encephalitis
  • Head injury or trauma

Upon diagnosis, thunderclap headaches will sometimes have no apparent cause.

Many experts consider SAH and the more recently-discovered RCVS to be the two most common causes of TCH.

Some of the causes listed above are related to one another.

For instance, sexual activity likely leads to blood vessel stress, which may trigger a thunderclap headache. I list both because blood vessel problems are a generalized cause of thunderclap headaches, but sexual activity is a very common, more specific cause of thunderclap headaches.

Diagnosis of Thunderclap Headaches

A diagnosis of thunderclap headaches is required to prescribe treatment, since treatment depends on the underlying cause of your thunderclap headache.

A doctor often uses the following 4 diagnostic tests to identify possible causes of a thunderclap headache (in order of importance):

  1. CT scan (computed tomography)
  2. Lumbar puncture (AKA spinal tap)
  3. MRI (magnetic resonance imaging)
  4. MRA (magnetic resonance angiography)

Treatments for Thunderclap Headache

How do you treat a thunderclap headache? There are 3 treatment options for thunderclap headaches:

  1. Surgery
  2. Psychotherapy
  3. Medication

The treatment for TCH your doctor will recommend depends on what is causing your TCH.

1. Surgery

In serious situations, your doctor may opt for surgery to treat what is causing your thunderclap headache.

Surgery may be necessary in treating the following TCH triggers:

  • Ischemic stroke
  • Hemorrhagic stroke
  • Aneurysmal subarachnoid hemorrhage
  • Aneurysm
  • Pituitary apoplexy
  • Encephalitis (if caused by tumors)
  • Meningitis

Side note: Meningitis is often a complication of spine or brain surgeries. Though usually treated with steroids or antibiotics, meningitis can also be treated with surgery, even though a surgery might have caused it in the first place.

Surgery is a very invasive operation, and sometimes expensive. But if your thunderclap headache is the result of any of the dire conditions listed above, surgery may be necessary to save your life.

2. Psychotherapy

Psychotherapy is the primary treatment for multiple personality disorder, which can lead to thunderclap headaches.

Psychotherapy may also help relieve the symptoms of a head injury, which may lead to a thunderclap headache.

All things considered, neither multiple personality disorder nor head injury is not the most common cause of TCH.

3. Medication

In non-life-threatening cases or after successful medical intervention, your doctor will likely prescribe medication to prevent future thunderclap headaches and the related complications.

Blood pressure medicine is a common pharmaceutical prescribed after a thunderclap headache. Blood pressure meds may lower blood pressure and increase blood flow.

Types of blood pressure medication:

  • ACE inhibitors
  • Alpha blockers
  • Alpha-2 receptor agonists
  • Angiotensin II receptor blockers
  • Beta-blockers

Nimodipine is a calcium channel blocker commonly prescribed to treat TCH triggers.

Verapamil is another calcium channel blocker that has shown success in treating TCH triggers.

Gabapentin is an anticonvulsant (AKA antiepileptic) that can treat TCH according to a small number of case studies. However, the mechanism by which gabapentin works against TCH is unknown.

NSAIDs (non-steroidal anti-inflammatory drugs) can reduce swelling and pain. NSAIDs may be prescribed if TCH is triggered by predictable and explainable reasons, like sexual activity or intense exercise.

Thunderclap Headache vs. Migraine

There are 3 main differences between a thunderclap headache and a migraine headache.

  1. Thunderclap headaches will be the worst headache pain you have ever experienced. Migraines are painful, but not as painful.
  2. Thunderclap headaches may recur in some cases, but migraines are much more likely to be a persistent issue.
  3. Migraines sometimes present with “aura”. Aura is a set of mainly visual symptoms, including flashing lights and dark spots. Thunderclap headaches do not present with aura.

Only a medical professional can diagnose whether your headache pain is a thunderclap headache or a migraine. But these 3 differences can give you a good idea of what to expect.

Complications & Other Conditions

Thunderclap headaches may be the symptom of a much more serious condition.

These are the complications that may occur or worsen when a thunderclap headache goes undiagnosed or untreated:

  • Recurrent thunderclap headaches
  • Severe pain
  • Issues in late-term pregnancy
  • Stroke
  • Death

How to Prevent Thunderclap Headaches

The most common cause of thunderclap headaches is blood vessel problems. The best way to prevent thunderclap headaches may be to keep your cardiovascular system in great shape.

Easy methods to maintain cardiovascular health, and therefore prevent TCH:

  • Exercise (at least 30 minutes of cardio 5 days a week)
  • Healthy diet (low in trans fat and sugars)
  • Manage stress
  • Do not drink excessive alcohol
  • Quit smoking

Because several possible TCH causes involve the spine, chiropractic care may also prove to be a useful prevention technique, particularly if you are already at risk.

Looking to the Future

If you or a loved one have a thunderclap headache, seek immediate medical attention at your local ER. A healthcare professional must determine whether it was caused by a stroke or another condition.

If you discover your headache is not a thunderclap headache, consider seeking chiropractic care for non-TCH headache pain. Migraines, in particular, can often be reversed by upper cervical chiropractic care.

At Denver Upper Cervical Chiropractic, we work with patients and employ gentle upper spine manipulation to work wonders for your quality of life. Click here to make an appointment!

  1. Yeh, Y. C., Fuh, J. L., Chen, S. P., & Wang, S. J. (2010). Clinical features, imaging findings and outcomes of headache associated with sexual activity. Cephalalgia30(11), 1329-1335. Abstract:
  2. Ferrante, E., Tassorelli, C., Rossi, P., Lisotto, C., & Nappi, G. (2011). Focus on the management of thunderclap headache: from nosography to treatment. The journal of headache and pain12(2), 251. Full text:
  3. Yang, C. W., & Fuh, J. L. (2018). Thunderclap headache: an update. Expert review of neurotherapeutics18(12), 915-924. Abstract:
  4. Valença, M. M., Andrade-Valença, L. P., Bordini, C. A., & Speciali, J. G. (2008). Thunderclap headache attributed to reversible cerebral vasoconstriction: view and review. The journal of headache and pain9(5), 277-288. Full text:
  5. Schwedt TJ. (2015). Thunderclap headache. CONTINUUM: Lifelong Learning in Neurology21(4), 1058-1071. Abstract:
  6. Zhang, L. M., Ren, L., Zhao, Z. Q., Zhao, Y. R., Zheng, Y. F., & Zhou, J. L. (2017). Surgical treatment for bacterial meningitis after spinal surgery: A case report. Medicine96(11). Full text:
  7. Makino, T., Kamitsukasa, I., & Ito, S. (2017). Reversible cerebral vasoconstriction syndrome due to atovaquone. Case reports in neurology9(3), 304-308. Full text:
  8. Garza, I., & Black, D. F. (2006). Persistent primary thunderclap headache responsive to gabapentin. The journal of headache and pain7(6), 419-421. Full text: