====== Thunderclap headache ======

see [[Benign Thunderclap headache]].
----
A **thunderclap headache (TCH)** is a severe headache that reaches peak intensity within **seconds to one minute** of onset. It is often described as the **worst headache of a person's life** and can be a symptom of a serious underlying condition, such as **subarachnoid hemorrhage** (SAH), or a benign primary headache disorder.

===== Key Features =====

- **Sudden onset**, reaching maximum intensity within **seconds to 1 minute**.

- **Severe intensity**, often described as **explosive, crushing, or unbearable**.

- May be associated with **nausea, vomiting, photophobia, neck stiffness, or neurological deficits**.

- Can occur spontaneously or be **triggered by exertion, sexual activity, coughing, or Valsalva maneuvers**.

===== Common Causes =====

**Serious Causes (Need Urgent Evaluation)**

1. **[[Subarachnoid hemorrhage]] (SAH) from a [[ruptured aneurysm]]**  

   - The most dangerous cause.

   - Often presents with a **sudden, severe headache**, loss of consciousness, vomiting, or neck stiffness.

   - Requires **urgent CT scan ± lumbar puncture**.

2. **Reversible cerebral vasoconstriction syndrome (RCVS)**  
   - Characterized by sudden, recurrent headaches over days/weeks.
   - May be triggered by **sexual activity, exertion, stress, or vasoactive drugs**.

3. **Cervical or intracranial artery dissection**  
   - Can cause **headache with neck pain and neurological symptoms** (e.g., Horner syndrome, stroke).

4. **Intracranial hemorrhage (other than SAH)**  
   - Hypertensive crisis or vascular malformations can cause sudden bleeding.

5. **Cerebral venous sinus thrombosis (CVST)**  
   - May present with headache, seizures, or focal neurological deficits.

6. **Meningitis or encephalitis**  
   - Accompanied by fever, altered mental status, and photophobia.

7. **Pheochromocytoma or hypertensive emergency**  
   - Sudden blood pressure surges can trigger severe headaches.

#### **Benign Causes (Diagnosis of Exclusion)**
- **Primary thunderclap headache** (idiopathic, but must rule out secondary causes first).
- **Primary sexual headache** (orgasmic headache).
- **Primary exertional headache**.
- **Primary cough headache**.

### **Evaluation & Diagnosis**
- **CT brain (non-contrast)** → First-line test for ruling out SAH.
- **Lumbar puncture** (if CT is negative but SAH is suspected).
- **MRI/MRA or CTA head and neck** → Evaluate for RCVS, dissection, or vascular pathology.

### **Management**
- **Emergency evaluation required** for any first-time TCH.
- **Treat underlying cause** if identified.
- **If benign (primary headache disorder)**, preventive medications like **indomethacin, propranolol, or calcium channel blockers** may be used.