by EBSCO Medical Review Board

Headache is pain in the head. A primary headache disorder is when there is no other cause. A secondary headache disorder is when the headache is due to another cause. Some primary types are:

Causes of secondary headache disorders may be:

  • Medicine
  • Infection
  • Bleeding
  • Head injury
  • Sinus problems
  • Too much pressure in the head from a growth, such as a tumor, or other problem

Tension Headache

These headaches happen when stress causes the muscles in the neck, face, and scalp to get tight and cause pain. They may only happen due to a stressful event. Or they may happen as often as every day. They can differ in how painful they are. The cause is not known.


This headache involves blood vessels, nerves, and chemicals in the brain. Eyesight problems, called auras, may come before them. These headaches can happen many times a week or once every couple of years. They may be so strong that they get in the way of normal tasks.

A trigger sets off a process that causes these headaches. The exact one is often not known. The nervous system may react to the trigger by making electrical activity that spreads across the brain. It may cause the brain to release chemicals that help regulate pain.

Cluster Headache

This is strong pain on one side of the head that keeps coming back. It follows a cluster or pattern.

There are two types. Either type may change to the other:

  • Episodic—(most common) one or more times each day for many months. Then, they go away and come back months or years later
  • Chronic—(less common) almost each day with, at most, one headache-free month a year

The cause is not known.

Sinus Headaches

Sinus headaches are from swelling of the sinuses. This is sinusitis. The sinuses are hollow parts of the skull. Colds and allergies cause swelling of the passages in the nose and can lead this. Allergies and viral infections cause mucus and cause tissue in the passages to swell. The passages become blocked and cannot drain. Mucus that is trapped may get infected with bacteria or, rarely, fungus. The swollen tissues or infection may cause pain and pressure.

What are the risk factors for headaches?What are the symptoms of headaches?How are headaches diagnosed?What are the treatments for headaches?Are there screening tests for headaches?How can I reduce my risk of getting headaches?What questions should I ask my doctor?Where can I get more information about headaches?


Cluster headache. EBSCO DynaMed website. Available at: Accessed March 9, 2022.

Headache information page. National Institute of Neurological Disorders and Stroke website. Available at: Accessed March 9, 2022.

Migraine in adults. EBSCO DynaMed website. Available at: Accessed March 9, 2022.

Tension-type headache. EBSCO DynaMed website. Available at: Accessed March 9, 2022.

Revision Information

  • Reviewer: EBSCO Medical Review Board Rimas Lukas, MD
  • Review Date: 11/2021
  • Update Date: 03/09/2022