Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: //medlineplus.gov/ency/patientinstructions/000424.htm

Headaches - danger signs

A headache is a pain or discomfort in the head, scalp, or neck.

Common types of headaches include tension headaches, migraine or cluster headaches, sinus headaches, and headaches that begin in your neck. You may have a mild headache with a cold, the flu, or other viral illnesses when you also have a low fever.

Some headaches are a sign of a more serious problem and need medical attention right away.

Emergency Causes of Headaches

Problems with blood vessels and bleeding in the brain can cause a headache. These problems include:

  • Abnormal connection between the arteries and veins in the brain that usually forms before birth. This problem is called an arteriovenous malformation, or AVM.
  • Blood flow to part of the brain stops. This is called a stroke.
  • Weakening of the wall of a blood vessel that can break open and bleed into the brain. This is known as a brain aneurysm.
  • Bleeding in the brain. This is called an intracerebral hematoma.
  • Bleeding around the brain. This can be a subarachnoid hemorrhage, a subdural hematoma, or an epidural hematoma.
  • Clots in the veins prevent blood flow from leaving the brain (sinus thrombosis).

Other causes of headaches that should be checked by a health care provider right away include:

When to Call the Doctor

If you cannot see your provider right away, go to the emergency room or call 911 (or the local emergency number) if:

  • This is the first severe headache you have ever had in your life and it interferes with your daily activities.
  • You develop a headache right after activities such as weightlifting, aerobics, jogging, or sex.
  • Your headache comes on suddenly and is explosive or violent.
  • Your headache is "the worst ever," even if you regularly get headaches.
  • You also have slurred speech, a change in vision, problems moving your arms or legs, loss of balance, confusion, or memory loss with your headache.
  • Your headache gets worse over 24 hours.
  • You also have fever, stiff neck, nausea, and vomiting with your headache.
  • Your headache occurs with a head injury.
  • Your headache is severe and just in one eye, with redness in that eye.
  • You just started getting headaches, especially if you are older than 50.
  • You have headaches along with vision problems and pain while chewing, or weight loss.
  • You have a history of cancer and develop a new headache.
  • Your immune system is weakened by disease (such as HIV infection) or by medicines (such as chemotherapy drugs and steroids).

See your provider soon if:

  • Your headaches wake you up from sleep, or your headaches make it difficult for you to fall asleep.
  • A headache lasts more than a few days.
  • Headaches are worse in the morning.
  • You have a history of headaches but they have changed in pattern or intensity.
  • You have headaches often and there is no known cause.

Alternative Names

Migraine headache - danger signs; Tension headache - danger signs; Cluster headache - danger signs; Vascular headache - danger signs

References

Digre KB. Headaches and other head pain. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 370.

Garza I, Robertson CE, Smith JH, Whealy MA. Headache and other craniofacial pain. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 102.

Russi CS, Walker L. Headache. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 17.

Review Date 11/9/2021

Updated by: Joseph V. Campellone, MD, Department of Neurology, Cooper Medical School at Rowan University, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

Related MedlinePlus Health Topics