A headache is pain or discomfort in the head or face. Headaches vary greatly in terms of the location and intensity of the pain, and how often they occur. Almost all people have headaches during their life. The brain tissue doesn't have pain-sensitive nerve fibers and doesn't feel pain. But other parts of the head can be responsible for a headache, including:

• A network of nerves that extends over the scalp.
• Certain nerves in the face, mouth, and throat.
• Muscles of the head, neck, and shoulders.
• Blood vessels found along the surface and at the base of the brain.

While headaches can sometimes indicate a serious medical or neurological condition, headaches do not usually pose any serious risk. Different types of headaches and their most common symptoms are described below.

In migraines, symptoms other than pain occur as part of the headache. These may include nausea and vomiting, lightheadedness, sensitivity to light (photophobia) and sound (phonophobia), and other visual symptoms. Migraines also have distinct phases. But not all people have each phase. The phases of a migraine headache may include:

• Premonition or prodromal phase. A change in mood or behavior may occur hours or days before the headache.
• Aura phase. A group of visual, sensory, or motor symptoms can precede the headache. Examples include vision changes, hallucinations, numbness, changes in speech, and muscle weakness.
• Headache phase. This is the period during the actual headache with throbbing pain on one or both sides of the head. Sensitivity to light and motion are common, as are depression, tiredness (fatigue), and anxiety.
• Resolution phase. Pain gets less during this phase but may be replaced with tiredness, irritability, and trouble concentrating. Some people feel refreshed after an attack, others don't.

Tension headaches are the most common type of headache. Stress and tight muscles are often factors in tension-type headaches. These are common symptoms of a tension-type headache:

• Slow onset of the headache
• Head usually hurts on both sides
• Pain is dull or feels like a band or vice around the head
• Pain may be in the back part of the head or neck
• Pain is mild to moderate, but not severe

Tension-type headaches typically don't cause nausea, vomiting, or sensitivity to light.

Cluster headaches usually occur in a series that may last weeks or months.

These are the most common symptoms of a cluster headache:

• Severe pain on one side of the head, usually behind one eye
• The eye that is affected may be red and watery with a droopy lid and small pupil
• Swelling of the eyelid
• Runny nose or congestion
• Swelling of the forehead

Headaches are classified as primary or secondary.

• A primary headache means the headache itself is the main health problem. But other factors, such as muscle tension or exposure to certain foods or beverages, may be triggers. Other things that may help cause the headache include medicines, dehydration, alcohol, or hormone changes.
• A secondary headache is related to an underlying health condition. An example of this would be a headache caused by a neck injury, eye problems, or an infection in the jaw, teeth, or sinus.

Headache symptoms depend on the type of headache. The frequency of headaches and the intensity of the symptoms may vary, too. See the different types of headaches and their most common symptoms listed above.

The symptoms of a headache may look like other health conditions. Always see your doctor for a diagnosis.

Your doctor will ask about your health history. They will also do a physical exam and certain tests.

Questions commonly asked during the exam may include:

• When do headaches occur?
• Do you have specific symptoms before the pain starts?
• What is the location of the headache?
• What do the headaches feel like?
• How long do the headaches last?
• Have there been changes in behavior or personality?
• Do changes in position or sitting up cause the headache?
• Do you have trouble sleeping?
• Do you have a history of stress?
• Do you have a history of head injury?
• Do you have other symptoms during a headache?

If your doctor suspects migraine or tension-type headaches and the nervous system exam is normal, you may not need any further testing. But if it's not a primary type headache, or if you have uncommon symptoms, other tests may be done to find the cause.

Tests used to find the cause of a headache may include:

• Blood tests. Various blood and other tests may be done to check for underlying conditions.
• Sinus X-rays. This imaging procedure looks for congestion or other problems that may be treated.
• MRI. This is a test that uses a combination of large magnets, radio waves, and a computer to produce detailed images of organs and structures within the body.
• CT scan. This imaging test uses X-rays and computer technology to make detailed images of the body. A CT scan shows detailed images of bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.
• Spinal tap (lumbar puncture). This may be done to rule out inflammation, infection, or high pressure in the spinal fluid.

The goal of treatment is to stop headaches from occurring. Good headache management depends on finding what type of headache you have. Management may include:

• Staying away from your known triggers, such as certain foods and beverages, lack of sleep, and fasting.
• Changing eating habits.
• Exercising.
• Resting in a quiet, dark environment.
• Taking medicines as recommended by your doctor.
• Controlling stress.

Migraine and cluster headaches may need specific medicines. These include:

• Abortive medicines. These are medicines prescribed by your doctor. They act on certain receptors in nerves and blood vessels in the head to stop a headache in progress.
• Rescue medicines. These medicines include pain relievers bought over the counter to stop the headache.
• Preventive medicines. These medicines are prescribed by your doctor. They are taken daily to stop a headache from starting.

Some headaches may need medical attention right away. This may include a hospital stay for observation, diagnostic testing, or even surgery. Treatment depends on the condition causing the headache. Full recovery depends on the type of headache and other health problems you may have.

If you know what sets off your headache, staying away from the trigger can prevent a headache. Reducing stress can ease or prevent headaches caused by stress. Migraine and cluster headaches may be prevented by taking a daily preventive medicines.

Most headaches can be managed with over-the-counter pain relievers. But call your doctor right away if you have a severe headache plus:

• A stiff neck.
• A fever.
• Nausea.
• Vomiting.
• Convulsion.
• Shortness of breath.
• Confusion.
• Muscle weakness.
• Double vision.
• A change in level of consciousness.
• Loss of vision or sensation.

Symptoms that may suggest a more serious headache include:

• The worst headache ever, or a new type of headache.
• Recurring headaches in children.
• Headaches that start early in the morning.
• A headache that follows a head injury.
• Pain that gets worse with strain, such as a cough or a sneeze.
• Vomiting without nausea.
• A sudden onset of pain.
• A headache that is becoming more severe or continuous.
• Personality changes.
• Seizures.

• A headache is pain or discomfort in the head or face area.
• Types of headaches include migraine, tension, and cluster.
• Headaches can be primary or secondary. If it's secondary, it's caused by another condition.
• Staying away from your headache triggers is the best prevention.
• Mild to moderate headaches can be managed with over-the-counter medicines, but tell your doctor if your headache is severe, and you have other symptoms.

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your doctor tells you.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you.
• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are and when they should be reported.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your doctor if you have questions, including on weekends and holidays.