What Is SUNCT Syndrome?

Imagine a pain that strikes like lightning — behind one eye, sharp and electric — then vanishes almost as quickly as it came. It lasts only seconds, but it’s enough to stop a conversation, interrupt a meal, or make you afraid to move your face. Then it happens again. And again. Sometimes dozens or even hundreds of times a day.

That’s the reality of SUNCT syndrome, one of the rarest and most painful headache disorders known. It’s a mouthful of a name — Short-lasting, Unilateral, Neuralgiform headache attacks with Conjunctival injection and Tearing — but it describes the core of what happens: short bursts of one-sided head pain that come with redness and tearing of the eye.

Because it’s so rare and looks a bit like other types of head pain, SUNCT is often misdiagnosed for years. For people who already live with chronic pain or other neurological conditions, finally putting a name to it can feel like both a relief and a new challenge.

Quick Overview

• SUNCT syndrome causes short, stabbing, one-sided headaches that come with eye redness and tearing.

• It belongs to a family of conditions called trigeminal autonomic cephalalgias (TACs) — disorders that affect both facial pain pathways and the body’s autonomic nervous system.

• Attacks last seconds to a few minutes, but can occur many times per day.

• It’s extremely rare, affecting an estimated 1 to 9 people per 100,000.

What SUNCT Feels Like

People who live with SUNCT often describe the pain as sharp, electric, or stabbing, centered around or behind one eye. It’s sudden and severe — the kind of pain that makes you freeze in place until it passes.

During an attack, one side of the face may flush or tear up. The eye might redden, the nose may run, or the eyelid can swell slightly. Sometimes, even small movements like chewing or talking can trigger another burst.

While each attack is short, the repetition can make daily life exhausting. Some describe it as living on edge, never knowing when the next jolt will come. The unpredictability can be as difficult as the pain itself.

How SUNCT Differs From Other Headaches

SUNCT is sometimes mistaken for migraine or cluster headache, but its pattern sets it apart:

The difference may seem subtle on paper, but for those who’ve experienced it, SUNCT pain feels entirely distinct — like an electrical storm behind the eye that strikes without warning.

What Causes SUNCT?

The exact cause isn’t fully understood, but scientists know SUNCT involves the trigeminal nerve (responsible for facial sensation) and the autonomic nervous system, which controls things like tearing, blood vessel dilation, and sweating.

Imaging studies show that the posterior hypothalamus — a small part of the brain that regulates timing and automatic responses — lights up during attacks.

In some rare cases, SUNCT can be secondary, caused by another condition, like:

• A small blood vessel pressing on the trigeminal nerve

• Brain lesions or tumors

• Structural abnormalities near the brainstem

For most people, however, SUNCT occurs on its own, with no clear underlying cause.

Getting a Diagnosis

SUNCT is diagnosed through careful observation and exclusion of other disorders. The main features include:

• One-sided, orbital, or temple pain

• Very short attacks (typically 5–240 seconds)

• Eye redness and tearing on the same side as the pain

• High attack frequency (dozens or more per day)

• No other identifiable explanation

Because SUNCT looks similar to several other headache types, a neurologist or headache specialist usually orders MRI imaging to rule out structural causes.

Many people spend years being told they have sinus issues, migraines, or even dental pain before finally hearing the term “SUNCT.” Getting the right diagnosis can feel like uncovering the missing piece of a puzzle.

Treatment Options

Treating SUNCT can be tricky, but some medications and procedures can reduce the frequency or severity of attacks.

Commonly used treatments include:

• Lamotrigine, which has the most consistent results across studies

• Topiramate, Gabapentin, or Oxcarbazepine, which help calm overactive nerves

• Intravenous lidocaine, sometimes used in hospital settings to break a severe attack cycle

If medication isn’t enough, doctors may explore:

• Nerve blocks near the trigeminal area

• Deep brain stimulation targeting the hypothalamus

• Microvascular decompression surgery, when imaging shows nerve compression

Because SUNCT is so rare, most people need care from a specialist center that regularly treats rare headache disorders.

Living With SUNCT

Living with any chronic or rare pain condition means juggling uncertainty, exhaustion, and hope — sometimes all at once. SUNCT adds another layer: its attacks are brief, but the anticipation of them can stretch across an entire day.

Some people describe avoiding activities that might trigger pain: skipping hot showers, chewing on one side, speaking less, or even holding their head a certain way. Others say that finally getting a diagnosis — and realizing they’re not imagining it — helps them reclaim some control.

There’s no one-size-fits-all approach to managing SUNCT. But keeping a headache diary, seeking specialist care, and connecting with supportive communities can make the journey more bearable.

For many, simply knowing this disorder exists is a form of validation — proof that the strange, shocking pain they feel has a name, and that doctors and researchers are studying it.

When to See a Doctor

Talk to a healthcare provider or neurologist if you experience:

• Sudden, one-sided pain near or behind one eye

• Attacks that last seconds or minutes but happen repeatedly

• Redness, tearing, or swelling on the same side as the pain

• New patterns of head pain that don’t fit your usual symptoms

Even if the episodes are short, tracking their pattern and triggers can give your doctor crucial clues. The right diagnosis can change not only your treatment plan, but also your sense of peace.

Key Takeaways

• SUNCT syndrome is a rare but severe headache disorder involving short, stabbing pain around one eye.

• Attacks are one-sided, brief, and often come with redness and tearing.

• The condition affects the trigeminal and autonomic nerves, creating sudden bursts of pain that can repeat many times daily.

• Treatment may include lamotrigine or other nerve-stabilizing medications, nerve blocks, or specialized procedures.

• Because it’s rare and easily mistaken for other headaches, seeing a headache specialist is essential.