What is a secondary headache, and how can you tell the difference between primary and secondary headaches? Learn how secondary headaches differ from conditions like migraine and cluster headache.
A headache is considered secondary when it is caused by another condition. The term “secondary” is used to distinguish these types of headache from primary headache disorders like migraine, tension-type headache or cluster headache, which just happen, without any known underlying cause.
What causes secondary headaches?
Causes of secondary headaches include medical conditions, such as severe high blood pressure, or neurologic conditions that affect the brain and its surrounding membranes, such as meningitis. Other infections of the head and neck, including pharyngitis and sinusitis, can also cause headache. Head trauma, even if it is mild, can often lead to headache.
Anything that takes up space inside the head can cause headache, including tumors and pooling of blood (such as subdural hematomas). Thunderclap headache — defined as a severe headache that reaches maximal intensity in under 60 seconds — can be caused by the rupture of an intracranial aneurysm (a weakened blood vessel in the brain) and the resulting internal bleeding (called a subarachnoid hemorrhage).
Differences Between Primary and Secondary Headache
Distinguishing primary from secondary headache is the most important first step in managing any headache symptoms. Some red flags that may alert your doctor to a potential secondary cause of head pain include associated systemic symptoms (such as fever), sudden changes in headache frequency or characteristics (particularly in elderly patients), “positional” headaches (headaches that consistently worsen when you stand up or lie down), and any abnormal findings on a physical examination.
Other features that may be associated with secondary headaches:
- Worst headache of your life
- Abrupt onset of headache without any warning or build-up
- Significant change in the pattern of recurrent headaches
- Headaches beginning earlier than 5 years old
- New headaches starting after 50 years old
- The presence of active cancer
- The presence of HIV
- New or severe headaches during pregnancy
- Headache associated with fever
- Headache associated with seizure
- Headache triggered by exertion, sex or Valsalva (straining)
Features more consistent with primary headaches:
- Stable pattern of headache over many months or years
- Long-standing headache history
- Family history of similar headaches
- Normal physical exam
Talk to your doctor if you have concerns that your headache may be due to some other medical condition. To develop an effective treatment plan for headache, it’s important to first be confident that there is no secondary cause for your symptoms.
This article is a legacy contribution from the American Headache Society Committee for Headache Education (ACHE) and the Fred Sheftell, MD Education Center.
