Chapter 2, Episode 3: What are Primary and Secondary Headache Disorders?


This content has been medically reviewed by Dr. Jihan Grant.

Headache types are classified as either primary or secondary. Primary headaches cannot be attributed to another disorder or cause. Secondary headaches are caused by other medical issues. This distinction is important to make as some secondary headaches are caused by medical emergencies that should be treated. Luckily, secondary headaches are less prevalent than primary headaches.

Primary headache disorders include migraine, tension headache, and trigeminal autonomic cephalgias, which we discuss in some of our other videos. Here we will talk about hypnic headache, primary stabbing headache, sex headache and thunderclap headache which are less common primary headache types.

Hypnic headaches, also known as “alarm clock headaches”, wake a person from sleep. These attacks commonly occur several times per week, around the same time of night. The headaches typically last 15 minutes to 4 hours after awakening and are more prevalent in those over 50 years old. 

Primary stabbing headaches, also known as “ice pick headaches”, are characterized by a sudden sharp or stabbing jolt of head pain that usually lasts for just a few seconds and typically switches locations in the head. They may also occur as a series of stabbing pains. 

Thunderclap headache refers to an excruciating headache that occurs suddenly. The pain typically peaks within 60 seconds. It is commonly described as “the worst headache of someone’s life.” While thunderclap headaches are classified as primary headaches, there are some secondary headaches that present the same way and can be an indicator of a medical emergency, such as an expanding or ruptured aneurysm, an arterial dissection, or a hemorrhagic stroke. 

Sex headaches typically occur with a sudden onset during sexual activity and intensify as sexual excitement increases. Sex headaches commonly occur on both sides of the head. It is important for a physician to rule out other potentially dangerous causes after (de-emphasize) a person experiences a headache with sexual activity for the first time, as vascular abnormalities can often cause similar symptoms.

Secondary headaches are caused by factors like concussions, brain tumors, viruses, strokes, meningitis, or over use of pain medication. But let’s discuss two secondary headache types: high and low pressure headaches.

High pressure headaches are caused by increased cerebrospinal fluid pressure and occur when there is overproduction or under absorption of cerebrospinal fluid in the head. This leads to increased pressure on the meninges, brain and the nerves in the eyes. 

Low pressure headaches are caused by low cerebrospinal fluid pressure and typically occur when cerebrospinal fluid leaks from a hole or tear in the dura. The dura is made of connective tissue that protects the brain and spinal cord. When the cerebrospinal fluid leaks out, the brain is not cushioned as well and can sit lower in the skull, causing headaches and other symptoms such as vertigo. The headaches can range from mild to debilitating. Often a person will feel better when lying flat. 

If you are experiencing a new headache, seek medical attention. While headaches are not typically a sign of concern, they could be the result of something concerning or life-threatening. 

For more information on headache disorders, visit

*The contents of this video are intended for general informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Always seek the advice of a physician or other qualified health provider with any questions you may have regarding a medical condition. AMD does not recommend or endorse any treatment, products, or procedures mentioned. Reliance on any information provided by this content is solely at your own risk.