Exploding head syndrome is a condition that happens during your sleep. The most common symptom includes hearing a loud noise as you fall asleep or when you wake up. Despite its scary-sounding name, exploding head syndrome usually isn’t a serious health problem.

While its exact cause is unknown, it belongs to a group of conditions called parasomnias, which are sleep disorders that wake you up from a partial or deep sleep. Nightmares, night terrors, and sleepwalking are also parasomnias.

If you have exploding head syndrome, you’ll hear loud explosion-like noises as you’re drifting off to sleep or around when you’re waking up. The former is a type of hypnogogic hallucination, and the latter is a type of hypnopompic hallucination. Although they’re only hallucinations, which are imagined, the noises in exploding head syndrome feel very realistic at the time they occur.

These noises may jolt you awake and keep you from falling back to sleep. It might happen only once, or you may have recurring experiences. The loud noise typically only happens when you’re going between sleep stages and usually goes away once you’re awake.

Some people also see flashes of light along with the loud noises. Other additional symptoms include:

  • elevated heart rate
  • sense of fear or distress
  • muscle twitches

The causes of exploding head syndrome aren’t fully understood. Some researchers believe it’s a neurological issue, while others think it’s related to clinical fear and anxiety. It could also be related to the components of your middle ear shifting during the night.

People with high stress levels or a history of other sleep interruptions seem to be at a higher risk of having exploding head syndrome. While doctors used to think it was more common in older adults and women, newer research suggests it’s fairly common in college students as well.

If you have symptoms of exploding head syndrome, you doctor might refer you to a sleep specialist. You may be asked to keep a sleep diary of your symptoms, as well as keep track of your dietary habits and emotional states, every night for a few weeks.

In some cases, you may need to spend a night in a sleep laboratory. There, a sleep specialist can conduct polysomnographic testing to evaluate various things happening in your body simultaneously while you sleep. This includes your neurological activity with an electroencephalogram, to try to pinpoint the cause.

There’s no standard treatment for exploding head syndrome. Your treatment plan will depend on your age, other symptoms, and the degree to which your symptoms impact your life.

For some, certain types of medication can help. These include medications that influence neurological activity, such as anticonvulsants and tricyclic antidepressants. Calcium channel blockers may also help.

Other treatment solutions include:

For some people, simply finding out that this condition is generally not harmful and not a reason to be overly concerned is enough to improve symptoms.

The symptoms of exploding head syndrome aren’t dangerous by themselves. For some people, however, the associated sensation of being jolted awake in fear can lead to ongoing anxiety. In some cases, this anxiety makes it very hard to fall asleep, which can lead to physical and psychological problems in time.

Exploding head syndrome can be frightening, especially the first few times you experience symptoms. Try to reduce your stress level, especially before you go to bed. If it happens regularly or starts to affect your sleep schedule, contact your doctor and ask about seeing a sleep specialist.