Severe Headaches

Overview

A severe headache is head pain intense enough to interrupt your normal activities, force you to lie down, or feel far worse than your usual headaches. Most severe headaches are caused by primary headache disorders such as migraine or cluster headache, which are painful and disabling but not dangerous to the brain.

A small number of severe headaches, however, are a sign of a serious or life-threatening problem such as bleeding around the brain, meningitis, or dangerously high blood pressure. The key is recognizing the warning features that separate a bad-but-benign headache from one that needs emergency care. A headache that comes on like a sudden thunderclap, or is the worst of your life, should never be ignored. It also helps to know your own usual pattern, because a headache that is clearly different from any you have had before is one of the most important warning signs.

Common Causes

Severe head pain has many possible causes. The most common are primary headaches, but secondary causes must always be considered when pain is sudden or unusual:

• Migraine: Throbbing, often one-sided pain with nausea and sensitivity to light and sound.
• Cluster headache: Excruciating pain around one eye, in repeated attacks.
• Tension headache: A tight, band-like pressure, usually milder but sometimes severe.
• Sinus infection: Pressure and pain over the cheeks and forehead.
• Medication-overuse headache: Frequent painkiller use that paradoxically causes daily headaches.

Serious causes that require urgent attention include bleeding in or around the brain (such as a subarachnoid hemorrhage), meningitis or encephalitis (infection), stroke, a very high blood pressure crisis, head injury, and, rarely, a brain tumor. A sudden, severe "thunderclap" headache is a medical emergency until proven otherwise.

Associated Symptoms

The symptoms accompanying a severe headache help tell apart routine causes from dangerous ones. Reassuring features include a familiar pattern, response to usual treatment, and nausea or light sensitivity typical of your migraines. Warning symptoms that point to an emergency include:

• Sudden onset reaching maximum pain within seconds to a minute
• The worst headache of your life
• Stiff neck, high fever, or a rash
• Confusion, drowsiness, or difficulty speaking
• Weakness, numbness, or vision loss
• Seizure, fainting, or repeated vomiting
• Headache after a head injury

If any of these occur, call emergency services without delay.

Diagnosis & Evaluation

A clinician first decides whether the headache could be dangerous based on its onset, pattern, and accompanying symptoms. Evaluation may include:

• A detailed history and neurological exam to check strength, reflexes, vision, and coordination.
• Brain imaging (CT or MRI) when a serious cause is suspected, especially with a sudden or worst-ever headache.
• A lumbar puncture (spinal tap) if meningitis or certain bleeds are possible.
• Blood pressure and blood tests to look for infection or other triggers.

For recurring headaches without danger signs, the diagnosis is often made from the pattern alone, and a headache diary can help identify the type and triggers.

Treatment & Management

Treatment depends entirely on the cause. Emergency causes are treated urgently in the hospital. For common headache disorders, options include:

• Acute relief: Over-the-counter pain relievers, or migraine-specific drugs such as triptans for migraine attacks.
• Rest in a dark, quiet room and hydration during a migraine.
• Preventive medicines for people with frequent or severe attacks.
• Treating the trigger, such as antibiotics for a sinus infection.

Avoid taking pain relievers too often, since overuse can cause rebound headaches that become a daily problem. Keeping a headache diary that notes timing, triggers, foods, sleep, and stress can reveal patterns and guide both diagnosis and prevention. If your usual treatment stops working or headaches become more frequent or severe, see a clinician to reassess.

When to See a Doctor

Call emergency services immediately for a headache that:

• Comes on suddenly and severely (thunderclap), peaking within a minute
• Is the worst headache of your life
• Comes with stiff neck, fever, rash, confusion, or seizure
• Causes weakness, numbness, trouble speaking, or vision loss
• Follows a head injury or a recent fall

See a doctor soon, even without emergency signs, if headaches are new after age 50, change in pattern, wake you from sleep, or steadily worsen over days to weeks.

Related Topics

Frequently Asked Questions

References

1. National Institute of Neurological Disorders and Stroke (NINDS). Headache Information.
2. Mayo Clinic. Headache — Symptoms and causes.
3. MedlinePlus, U.S. National Library of Medicine. Headache.
4. American Migraine Foundation. Understanding Migraine.