Headaches may occur bilaterally, unilaterally, or travel across the head. A headache may be sharp, throbbing or dull. They may appear gradually or suddenly and may last from minutes to several days. Usually, headaches do not result from a serious illness, but sometimes they may be a life-threatening, necessitating emergency care.
Over-activity of or malfunction of pain-sensitive structures in your head causes a primary headache. It is not a symptom of an underlying disease. The brain’s chemical activity, the nerves or blood vessels encircling the skull, or the muscles of your head and neck can play a role in primary headaches. Sometimes genetics make it more likely to develop such headaches.
Common primary headaches are
Primary headaches that could be a symptom of an underlying disease include:
- exercise headaches, and
- cough headaches.
Primary headaches can be triggered by lifestyle factors such as
A secondary headache is a symptom of a disease that can activate the pain-sensitive nerves of the head.
- acute sinusitis,
- carotid artery or vertebral artery dissections,
- brain aneurysm,
- brain arteriovenous malformation,
- brain inflammation (encephalitis),
- Brain tumor,
- carbon monoxide poisoning,
- Chiari malformation,
- dental issues,
- ear infection,
- febrile illnesses,
- high blood pressure,
- increased pressure within the skull (pseudotumor cerebri),
- inflammation of the arteries in the brain (giant cell arteritis),
- influenza (flu),
- intracranial hematoma (bleeding in or around the brain),
- monosodium glutamate (MSG),
- overuse of pain medication,
- panic attacks,
- post-concussion syndrome,
- pressure from tight headgear,
- Trigeminal neuralgia and other neuralgias of nerves joining the brain and face, and
- venous thrombosis (blood clot within the brain).
Some secondary headaches include:
- external compression headaches from pressure-causing headgear;
- ice cream headaches (brain freeze);
- sinus headaches (caused by congestion in sinus cavities), and
- spinal headaches (caused by a spontaneous cerebrospinal fluid leak, spinal tap, epidural, or spinal block).
A headache can be a symptom of a serious condition, such as a stroke, meningitis or encephalitis.
Go to a hospital emergency room or call 911 if experiencing the most severe headache of your life, a sudden headache or a headache accompanied by
- difficulty seeing;
- difficulty speaking and understanding speech;
- difficulty walking;
- fever greater than 102 F (39 C);
- nausea or vomiting;
- numbness, weakness or paralysis; and
- stiff neck.
See a doctor if your headaches:
- occur more often than usual;
- are more severe than usual;
- do not improve with over-the-counter drugs; and
- keep you from working, sleeping or taking part in normal activities of daily living.
Jose Veliz MD is the medical director of Palomar Spine & Pain, in Escondido, CA (North San Diego County).