Almost everyone gets headaches. A lot of the time, they're caused by something simple — such as staying up too late, running around in the sun too long, or the stress of a big exam. But some people get headaches that come often or last for a long time.

So how do you know if a headache is just a passing pain or something more? And what should you do about it?

Anatomy of a Headache

Although it may feel like it, a headache is not actually a pain in your brain. The brain tells you when other parts of your body hurt, but it can't feel pain itself.

Most headaches happen in the nerves, blood vessels, and muscles that cover a person's head and neck. Sometimes the muscles or blood vessels swell, tighten, or go through other changes that stimulate the surrounding nerves or put pressure on them. These nerves send a rush of pain messages to the brain, and this brings on a headache.

Different Kinds of Headaches

The most common type of headache is a tension, or muscle-contraction, headache. This happens when stressed-out head or neck muscles keep squeezing too hard. With this kind of headache, the pain is usually dull and constant. It might feel as though something is pressing or squeezing on the front, back, or both sides of your head.

Sometimes people also get headaches when they are sick — you may have had a sinus headache when you've had a cold, flu, or allergies, for example.

People who drink a lot of caffeinated drinks might get caffeine-withdrawal headaches. And some headaches are the side effect of taking a particular medication.

Pain that's especially sharp and throbbing can be a sign of a migraine headache. Migraine headaches aren't as common as tension headaches. But for teens who do get them, the pain can be strong enough to make them miss school or other activities if the headaches aren't treated. Fortunately, doctors know more about what causes migraines and have better ways to treat them than they did just a few years ago.

One big difference between tension headaches and migraines is that migraines sometimes cause people to feel sick or even to throw up. Tension headaches typically don't cause nausea or vomiting, and they're usually not made worse by physical activity — which is another thing that can happen with migraines. Most migraines last anywhere from 30 minutes to 6 hours. Some can last as long as a couple of days.

Strong headache pain can be frightening for people who haven't had it before. But it's rare that a headache is a sign of something serious. If something is wrong — like a brain tumor or meningitis — the person will most likely notice other signs as well.

What Causes Headaches?

Lots of different things can bring on headaches. Most headaches are related to:

• stress
• dehydration
• computer or TV watching
• loud music
• smoking
• alcohol
• caffeine
• skipping meals
• lack of sleep
• a bump to the head
• taking a long trip in a car or bus

The following kinds of infections can also bring on headaches in some people:

• flu
• sinus infections
• strep throat
• urinary tract infections
• ear infections
• Lyme disease

For some teens, hormonal changes can also cause headaches. For example, some girls get headaches just before their periods or at other regular times during their monthly cycle.

Migraine headaches often are hereditary. So if a parent, grandparent, or other family member gets them, there's a chance you may get them too (but that doesn't mean you will get them). Certain things (called triggers) are known to bring on migraine headaches in people who are predisposed to getting them. Some of the things that can trigger migraines are certain foods, stress, changes in sleep patterns, or even the weather.

Getting Relief

Most headaches will go away if a person rests or sleeps. When you get a headache, lie down in a cool, dark, quiet room and close your eyes. It may help to put a cool, moist cloth across your forehead or eyes. Relax. Breathe easily and deeply.

If a headache doesn't go away or it's really bad, you may want to take an over-the-counter pain reliever like acetaminophen or ibuprofen. You can buy these in drugstores under various brand names — and your drugstore may carry its own generic brand. It's a good idea to avoid taking aspirin for a headache because it may cause a rare but dangerous disease called Reye syndrome.

If you are taking over-the-counter pain medications more than twice a week for headaches, or if you find these medicines are not working for you, it's a sign that you should talk to your doctor.

When to See a Doctor

If you think your headaches may be migraines, you'll want to see a doctor to treat them and learn ways to try to avoid getting the headaches in the first place. Sometimes relaxation exercises or changes in diet or sleeping habits are all that's needed. But if necessary, a doctor also can prescribe medication to control headaches.

It's very rare that headaches are a sign of something serious. But see a doctor if you have headaches more than three times a month or have a headache that:

• is particularly painful and different from the kinds of headaches you've had before
• doesn't go away easily
• follows an injury, such as hitting your head
• causes you to miss school

You'll also want to see a doctor if you have any of these symptoms in addition to a headache:

• changes in vision, such as blurriness or seeing spots
• tingling sensations along with the headache (for example, tingling sensations in the arms or legs)
• skin rash
• weakness, dizziness, or difficulty walking or standing
• neck pain or stiffness
• fever

If you do see a doctor for headaches, he or she will probably want to do a physical examination and get your medical history to help figure out what might be causing the headaches.

Sometimes pediatricians or family doctors will refer people with headaches they think might be migraines or a symptom of a more serious problem to a specialist like a neurologist, a doctor who specializes in the brain and nervous system.

The doctor may ask you about:

• how severe and frequent your headaches are
• when they happen (this helps decide if the headaches have a pattern or are connected to any specific foods or events)
• any medications you're taking
• any allergies you may have
• any stress you might be experiencing
• your diet, habits, sleeping patterns, and what seems to help or worsen the headaches

A doctor may also take blood tests or imaging tests, such as a CAT scan or MRI of the brain, to rule out medical problems.

Most headaches are not a sign that something more is wrong. But if you are bothered by frequent or intense headaches, there are lots of things a doctor can do — from recommending changes in your diet to prescribing medication — so you don't have to put up with the pain!

Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: April 2013