A hypnic headache is a type of headache that wakes people from sleep. They’re sometimes referred to as alarm-clock headaches.

Hypnic headaches only affect people when they’re sleeping. They often occur around the same time several nights a week.

Read on to learn more about hypnic headaches including how to manage them.

As with all headaches, the main symptom of a hypnic headache is pain. This pain usually throbs and spreads across both sides of your head. While the pain can range from mild to severe, it’s usually bad enough to wake you up when you’re sleeping.

These headaches usually occur at the same time of night, often between 1 and 3 a.m. They can last anywhere from 15 minutes to 4 hours.

About of the people who experience hypnic headaches have them every day, while others experience them at least 10 times a month.

Some people report migraine-like symptoms during their hypnic headaches, such as:

  • nausea
  • sensitivity to light
  • sensitivity to sounds

Experts aren’t sure what causes hypnic headaches. However, they seem to be a primary headache disorder, which means they aren’t caused by an underlying condition, such as a brain tumor.

In addition, some believe that hypnic headaches might be related to issues in the parts of the brain involved in pain management, rapid eye movement sleep, and melatonin production.

Hypnic headaches tend to affect people the age of 50, but this isn’t always the case. However, there’s usually a long period of time between when someone starts getting hypnic headaches and when they’re finally diagnosed. This could explain why people diagnosed with hypnic headaches are usually older.

Women also appear to have a higher risk of developing hypnic headaches.

If you think you’re getting hypnic headaches, make an appointment with your doctor. They’ll start by focusing on ruling out other possible causes for your headaches, such as high blood pressure.

Other conditions your doctor will want to rule out include:

Make sure to tell your doctor about any over-the-counter (OTC) or prescription medications you take, especially nitroglycerin or estrogen. Both of these can cause similar symptoms to hypnic headaches.

Depending on your symptoms and medical history, your doctor may perform any number of tests, such as:

  • Blood tests. These will check for signs of infection, electrolyte imbalances, clotting problems, or high blood sugar levels.
  • Blood pressure tests. This will help to rule out high blood pressure, which is a common cause of headaches, especially in older adults.
  • Head CT scan. This will give your doctor a better view of the bones, blood vessels, and soft tissues in your head.
  • Nocturnal polysomnography. This is a sleep test done in a hospital or sleep lab. Your doctor will use equipment to monitor your breathing patterns, blood oxygen levels, movements, and brain activity while you’re sleeping.
  • Home sleep tests. This is a simpler sleep test that can help to detect sleep apnea symptoms, another potential cause of a headache at night.
  • Brain MRI scan. This uses radio waves and magnets to create images of your brain.
  • Carotid ultrasound. This test uses sound waves to create images of the inside of your carotid arteries, which supply blood to your face, neck, and brain.

There are no treatments specifically designed to treat hypnic headaches, but there are a few things you can try for relief.

Your doctor will likely recommend you start by taking a dose of caffeine before bed. While it’s counterintuitive, most people with hypnic headaches have no problem sleeping after taking a caffeine supplement. Caffeine also carries the lowest risk of side effects compared with other treatment options.

To use caffeine to manage your hypnic headaches, try one of the following before going to bed:

  • drinking a strong cup of coffee
  • taking a caffeine pill

Learn more about the relationship between caffeine and migraines.

You can also try taking an OTC migraine medication, which usually contains both a pain reliever and caffeine. However, taking these long-term can cause chronic headaches.

Others find relief from taking lithium, a medication used to treat bipolar disorder and other mental health conditions. Topiramate, an anti-seizure medication, also helps some people prevent hypnic headaches. However, both of these medications can cause bothersome side effects, including fatigue and slowed reactions.

Other drugs that have worked for some people include:

Hypnic headaches are rare but frustrating, as they can prevent you from getting enough sleep. They can also be hard to diagnose since many conditions cause similar symptoms.

There’s no standard treatment for hypnic headaches, but consuming caffeine just before bed seems to work well for some cases. If this option doesn’t work for you, talk to your doctor about trying a new medication.