chapter 1
What Are the Different Types of Headaches?


In the first season of the TV show Lost, Sawyer, one of the main characters, experienced headaches. What caused these headaches seemed to be an easily solved mystery: He needed reading glasses, which he managed to find on that mysterious island.
If only all headaches could be cured so quickly. But given the many colorful, bizarre, and even scary names that various types of headaches go by, it's easy to be confused, or even terrified, by this common problem.
There are more than three hundred types of headaches listed in medical books though fewer than 10 percent have a known cause. Medical experts divide headaches into two general categories: primary and secondary.
Primary headaches aren't the result of any underlying condition or disease; these headaches are self-contained. In other words, once we've arrived at a diagnosis, there's no testing necessary, and we're ready to discuss treatment. Secondary headaches are the symptom of something else, typically a disease, trauma, or brain disorder. If we suspect a secondary cause, you'll need to undergo testing to uncover the principal issue. Of the two, secondary headaches are more worrisome, but this in no way trivializes the pain and suffering someone with a primary headache experiences.
By the way, one frequent concern we often hear from patients is that their head pain moves around. This is actually a good sign. It typically means that there is a benign process at work, and it is almost always a manifestation of a primary headache. It is a reflection that the brain itself, rather than a lesion or an expanding tumor, is causing the problem.
How a Diagnosis Is Made
Making a diagnosis of a primary headache problem like migraines, tension-type, or cluster headaches is not just a matter of ruling out other causes of headache. The International Classification of Headache Disorders (ICHD), which is considered the "bible" for doctors who make headache diagnoses, lists criteria that must be met before a headache diagnosis can be assigned. ICHD classifies headaches based on their predominant characteristics—for example, headaches that are one-sided with typical associated features such as nausea and vomiting generally fit in the "migraine" category. The different headaches may then be broken down into subtypes. Migraines, for instance, can occur with or without aura and can be episodic or chronic. Tension-type headaches can occur with or without muscle tension, and so on.
The ICHD headache categories and criteria were first developed based on the consensus of headache experts—headache is a clinical diagnosis, and there are no tests or X-rays that "prove" someone has a migraine. Instead, the experts identified patterns of symptoms that are common in those with migraines. (This might help you understand why your doctor asks such detailed questions about your headache symptoms when trying to make a diagnosis.)
The ICHD is a work in progress and will undoubtedly be updated periodically in the future although we don't think it's likely the criteria for migraines will change substantially. This is because the original criteria for diagnosing migraines and other disorders, such as cluster headaches, have stood the test of time quite well. Newer imaging techniques that allow us to see which parts of the brain are active during different types of headaches have in large part confirmed earlier expert opinion that these are two separate forms of headache.
Primary Headaches
Tension-type Headaches
Tension-type headaches are the most common type of headache, affecting more than three in four people at some point in their lives. We consider the term itself a misnomer because doctors don't believe that this type of headache is usually caused by muscle tension or stress. As a result, this is a very unsatisfactory and contested diagnosis. Many experts speculate that they are simply a milder form of migraines.
In our practice, we carefully explain the use of the diagnosis because it tends to carry a stigma. Mary came to us having been labeled a tension-headache sufferer several years ago, and one of the first things she told us is how much this bothered her. "It makes me sound like I don't deal well with stress, and I can't get my act together," she said during her initial examination.
As we explained to Mary and tell all patients with a similar syndrome, the diagnosis is not a reflection on how they handle their lives. Tension-type headache refers simply to a pattern of headache, a fairly nondescript headache without many of the classic features of migraines. Unlike migraine headaches, tension-type headaches are not often accompanied by other symptoms, such as nausea, vomiting, or blurred vision. The pain is mild or moderate. It may envelop your entire head or be limited to the forehead or to the back or top of your head. Many people describe the sensation as a dull tightness or pressure that occurs in a bandlike pattern (see Figure 1). The intensity of the pain may fluctuate, but most of the time it won't be severe enough to keep you from functioning or sleeping or to awaken you at night.
Tension-type headaches can occur infrequently, regularly, or daily. They are common at any age, but women are more susceptible: Their lifetime prevalence is 88 percent, versus 68 percent for men. Really, anyone can have one. The patients we see tend to have the bad ones.
Cluster Headaches
When Jay described his headache episodes, they were understandably frightening. As he ticked off the symptoms, it quickly became clear he suffered from a rare but painful class of head pain known as cluster headaches.
Jay's headaches begin suddenly, usually an hour or two after he falls asleep. The pain is intense, sharp, and penetrating, and it usually occurs behind one eye, which can get teary and bloodshot. His eyelid may droop, and the nostril on that side may first be stuffy, then runny. During a single attack, the symptoms can occur in either the left or right side but never in both.
Unlike someone with a migraine headache—who tends to lie quietly in bed—Jay must get up and pace the floor. The pain is so excruciating that it's tempting to bang his head against a wall. After an hour or two, the pain and other symptoms usually recede, sometimes just as suddenly as they came on. But they tend to recur at the same time day after day.
About ten times as many men as women have cluster headaches. About 85 percent of those affected by this type of headache have the episodic form: clusters of one or two headaches a day over a period of two to six weeks, alternating with headache-free stretches. The remission time between cluster periods is generally six to twelve months, but it can be as short as a few weeks or as long as several years. The other 15 percent of those with cluster headaches have the chronic form. In these cases, the attacks continue for at least a year without any remission.
Chronic Daily Headache Syndrome
Suzanne woke up with a headache nearly every day. She started having occasional mild head pain in her twenties, which gradually increased in frequency and intensity and now, in her early thirties, she came to see us for some relief.
Suzanne is among a significant minority of headache sufferers who have frequent headaches. Most people experience headaches only from time to time. But like Suzanne, about one in twenty people experience them daily or almost every day. And women are twice as likely as men to develop chronic daily headache.
Chronic daily headache is a broad term used to describe daily or near-daily headaches that can develop from a number of different causes. In two out of three cases, chronic daily headache develops in people who previously experienced only intermittent migraines, tension headaches, or other types of headaches. If the initial type of headache is known, doctors may use more specific diagnostic terms such as chronic migraine or chronic tension-type headache. In such people, the headaches tend to increase in frequency gradually—over the course of a decade or so—until they occur daily. In the remaining one-third of cases, chronic daily headache develops without warning, sometimes as a result of illness, surgery, or an injury to the head, neck, or back, and sometimes for no apparent reason.
Regardless of the cause, chronic daily headaches are notoriously difficult to treat and, understandably, often produce anxiety and depression. To make matters worse, about half of people with chronic daily headache syndrome also experience additional and more severe headaches on a regular basis.
Chronic daily headaches usually manifest in one of two distinct patterns. About half of those affected experience headaches that begin in the morning and worsen through the day, while one-quarter experience the reverse (pain that is worst in the morning and gradually diminishes). The remaining one-quarter experience a variable pattern, with pain sometimes diminishing and sometimes worsening as the day goes on.
The types of headaches you've had in the past may also affect symptoms once chronic daily headache develops. Suzanne described her daily headache pain as a steady, viselike grip with throbbing at the temples. Others have a sensory or visual disturbance known as an aura that may or may not diminish in frequency over time. Meanwhile, those with a history of tension-type headaches may sometimes develop nausea and vomiting, sensitivity to light and noise, and throbbing in the temples—hallmarks of migraines.
Exploding Head Syndrome
Despite its name, exploding head syndrome isn't actually dangerous; that is, there are no actual head explosions with this condition. A person with exploding head syndrome hears a very loud noise that seems to be coming from inside the head. There's no pain or other physical sensations though the noise can be terribly frightening. Like cluster headaches, exploding head syndrome typically comes on when you're asleep. This is a rare and poorly understood condition and technically is not even a headache disorder. Nonetheless, people with this condition often end up in the headache clinic looking for an explanation. Experts speculate that it may be caused by minor seizures affecting the brain's temporal lobe or a problem in the middle ear. Like so many headaches and other health problems, it seems that stress and fatigue play a role in its onset.
Migraine Headaches
Migraine pain has been called indescribable, yet 35 million Americans know it all too well. Twenty-eight million Americans—about one in five women and one in twenty men—have migraines. We think of a migraine as a "headache plus"; that is, a headache plus a lot of other symptoms. It's a total body syndrome, which horror author Stephen King, himself a migraineur, penned a vivid description of in his novel Firestarter:
The headache would get worse until it was a smashing weight, sending red pain through his head and neck with every pulse beat. Bright lights would make his eyes water helplessly and send darts of agony into the flesh just behind his eyes. Small noises magnified, ordinary noises insupportable. The headache would worsen until it felt as if his head were being crushed inside an inquisitor's lovecap.… He would be next to helpless.
Migraine is the French derivation of the Greek word hemikrania, meaning "half a head," referring to a typical pattern of migraine distress—pain only on one side of the head, most often at the temple (see Figure 2). The affected side can vary from one attack to the next or during a single episode. One-sided pain is a common but not invariable characteristic of migraines; plenty of sufferers experience bilateral or generalized head pain with migraines.
Unlike tension-type and sinus headaches, which produce a dull, steady pain, the pain of a migraine headache is throbbing or sharp. It is usually most severely in the area of the temple but may also affect the eye, or back of the head.
The pain ranges from moderate to severe. Unlike tension-type headaches, migraine headaches can keep you from functioning or sleeping, and they can even rouse you from sound slumber. Most people describe the pain as pulsating or throbbing. It can also be sharp, almost as if a dagger is piercing your temple or eye.
Nausea and vomiting are common during a migraine headache. Likewise, tense head, neck, and shoulder muscles can accompany a migraine headache. In most cases, this is thought to be an involuntary response to the pain rather than its cause (although it is probably the case that tight muscles can trigger a migraine headache). Bright lights and loud noises worsen the pain and may prompt someone with a migraine headache to seek out quiet, dimly lit places. Similarly, odors may aggravate nausea and vomiting.
About 20 percent of migraines begin with one or more neurological symptoms called an aura. Visual complaints are most common. They may include halos, sparkles or flashing lights, wavy lines, and even temporary loss of vision. The aura may also produce numbness or tingling on one side of the body, especially the face or hand. Problems with speech can also occur. Some patients develop aura symptoms without getting headaches; they often think they are having a stroke, not a migraine.
The majority of migraines develop without an aura. In typical cases, the pain is on one side of the head, often beginning around the eye and temple before spreading to the back of the head. The pain is frequently severe and is described as throbbing or pulsating. Nausea is common, and many migraine patients have a watering eye, a running nose, or congestion. If these symptoms are prominent, they may lead to a misdiagnosis of cluster or sinus headaches.
Without effective treatment, migraine attacks in adults usually last from four to seventy-two hours. When you're suffering a migraine, even four hours is far too long—and that's why early treatment is so important.
You might also experience a sort of migraine known as aura without headache. This includes many of the symptoms of migraine with aura minus the painful part. For many people, there are clear migraine stages. These include prodrome, with warning signals that a migraine is coming, such as changes in mood or appetite, aura (in about 20 percent of people with migraine), then postdrome, also known as a migraine hangover. Not everyone goes through all the stages—and in the case of aura without headache, the person skips the actual headache.
Secondary Headaches
Secondary headaches are actually symptoms of another health problem. Many non-life-threatening medical conditions, such as a head cold, the flu, or a sinus infection, can cause headache. Some less common but serious causes include bleeding, infection, or a tumor.
A headache can also be the only warning signal of high blood pressure, which your doctor may also refer to as hypertension. In addition, certain medications—such as nitroglycerin, prescribed for a heart condition, and estrogen, prescribed for menopausal symptoms—are notorious causes of headaches.
One particularly severe type of secondary headache is called a thunderclap headache. As its name implies, this is a very severe headache that comes on abruptly. It's hard to ignore and feels like someone punched you in the head. In some cases, the headache may start to fade after an hour–but it may last days.
Whether it improves promptly or not, it's important to get immediate medical attention if you suddenly experience a very severe headache, one you'd describe as "the worst headache of your life." Sudden, severe headaches can be a sign of bleeding in or around the brain, which can be deadly if not treated quickly. Fortunately, thunderclap headaches are not common. However, since it can be hard to tell the difference between dangerous and benign causes of thunderclap headaches, it's prudent to go to a doctor or hospital for evaluation.
Do you scream after ice cream?
One minute you're enjoying a delicious ice-cream cone; the next, you have "brain freeze." Generally, the headache is immediate and lasts for under a minute. It's usually a very sharp, steady pain felt in the center of the forehead, but it may also occur on one side.
The cause of cold-stimulus headache, stabbing headache, or "ice-cream headache," remains largely a mystery. One theory is that the pain originates in the back of the throat, which is chilled by the ice cream, but is felt in the head—a phenomenon known as referred pain. Any cold food or drink can induce this type of headache, but ice cream is the main culprit because it's very cold and is often swallowed quickly. This doesn't allow for the treat to be warmed slightly in the mouth before it contacts the back of the throat.
To the relief of ice-cream lovers, doctors don't prescribe abstinence for headache prevention. Instead, they suggest taking smaller bites and eating slowly, to give your mouth enough time to warm up the ice cream.
How to Think About Your Headaches
Although most people experience at least one headache annually, others suffer from recurring headaches: About 50 percent of people experience a headache at least once a month, 15 percent at least once a week, and 5 percent every day. But only a small fraction of these people ever seek a doctor's attention because most headaches disappear on their own or with the help of an over-the-counter pain reliever, rest, or a good night's sleep. Headaches that are severe, occur often, or are unresponsive to nonprescription pain relievers require medical attention.
When trying to classify your headaches, it helps to step back from each individual headache and think of your entire experience as a syndrome, so you can get a complete picture of your problem. For example, your most recent headache may have been fairly mild even though you endure a real whopper three to four times a year. In our practice we take great care to consider the whole picture to make a diagnosis.
Headaches don't always match their textbook descriptions, and yours may not exactly match any of the descriptions in this chapter. Often, the symptoms of different types of headaches can occur in conjunction. Many people suffer from a hybrid of tension and migraine headaches, which can cause confusion because there isn't a definitive test for either type of headache. A headache produced by stress or tight muscles can also resemble one caused by an underlying disease. To exclude more serious causes, when indicated, your doctor may perform additional tests, possibly including a computed tomography (CT) scan or a magnetic resonance imaging (MRI) scan of your head or neck.
It's also important to keep in mind that your pain patterns may not exactly fit any of the descriptions above—but it's a pretty safe bet that you have your own stereotypical and instantly recognizable pattern. In other words, you can always sense when your headache is coming on, and you have a pretty good idea of how it will play out. You can take care of many types of headaches by yourself, and your doctor can give you medication to control most of the tougher ones. But some headaches call for prompt medical care. You should know when a headache needs urgent care (see box here) and how to control the vast majority of headaches that are not threatening to your health.
Doctors don't fully understand what causes most headaches. They do know that the brain tissue itself and the bones of the skull are never responsible since they don't have nerves that register pain. But the blood vessels in the head and neck can signal pain, as can the tissues that surround the brain and some major nerves that originate in the brain. The scalp, sinuses, teeth, and muscles and joints of the neck can also cause head pain. For most of us, an occasional headache is nothing more than a temporary speed bump in the course of a busy day. But for some of us, headaches are a big problem.
Although headaches are rarely harbingers of more ominous disease, it makes sense to see your doctor if you're having a headache on a weekly basis, if your headaches interfere with your ability to function, or if they change in any particular way. Most likely, your headaches aren't a symptom of anything serious, but the peace of mind and possibility of effective treatment justify the time and expense of a medical evaluation. In the case of migraines, it's more than just peace of mind. You deserve to be appropriately diagnosed and treated.
When to Worry
You can take care of many types of headaches by yourself, and your doctor can give you medication to control most of the tougher ones. But some headaches call for prompt medical care. Here are some warning signs:
• Headaches that first develop after age fifty
• A major change in the pattern of your headaches
• An unusually severe "worst headache ever"
• Pain that increases with coughing or movement
• Headaches that get steadily worse
• Changes in personality or mental function
• Headaches that are accompanied by fever, stiff neck, confusion, decreased alertness or memory, or neurological symptoms such as visual disturbances, slurred speech, weakness, numbness, or seizures
• Headaches that are accompanied by a painful red eye
• Headaches that are accompanied by pain and tenderness near the temples in older individuals
• Headaches after a blow to the head
• Headaches that prevent normal daily activities
• Headaches that come on abruptly, especially if they wake you up
• Headaches in patients with cancer or impaired immune systems



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