What Causes It?
The cause of a thunderclap headache is not always immediately apparent. Occasionally, it can be completely benign, and may be connected with a recurring headache disorder such as migraine, or with a spike in blood pressure such as from an intense workout.
However, a thunderclap headache is often caused by an issue with blood vessels or arteries in the brain, including torn or ruptured blood vessels, a stroke (blocked or bleeding blood vessels), or a brain aneurysm (bulging or bleeding blood vessels). It could also be caused by a leakage of spinal fluid.
What Are the Symptoms?
Symptoms of a thunderclap headache are typically the same, regardless of the underlying cause. Head pain is sudden and severe — people often describe it as the worst headache they've ever had. It is most commonly felt like a sudden smack in the head, but may spread down the neck and into the back. Pain is most intense about a minute after it starts, and lasts at least five minutes.
Accompanying symptoms might include fever, numbness, weakness, speech problems, nausea or vomiting.
How Is It Diagnosed?
To distinguish a thunderclap headache from other headaches, a doctor may administer a CT-angiogram scan, an imaging test that provides a view of blood vessels in and around the brain. If testing does not show the head pain to be caused by an underlying issue, the diagnosis will likely be thunderclap headache.
How Is it Treated?
Treatment for thunderclap headaches depends on diagnosis of the cause. The physician must rule out a bleeding vessel. Subarachnoid hemorrhage (SAH) occurs during aneurysm, or in the case of an artery bleed. If bleeding continues uncontrolled, the brain is subjected to increasing pressure from it, so speedy intervention is required.
If the diagnosis is simply thunderclap headaches and/or the cause of the pain is not serious or life-threatening, it can be managed with over-the-counter painkillers or with headache medication prescribed by a doctor.
Is it Preventable?
Because they occur suddenly and without warning, thunderclap head pain can be difficult to prevent. Managing underlying health conditions with a doctor's guidance and maintaining a healthy lifestyle may be the best ways to avoid them. A nutritious diet and active lifestyle, for example, can help keep blood pressure from rising to levels that could encourage a thunderclap headache.