Facts and Definition of Cluster Headache
- A cluster headache belongs to the primary headache classification system, and is the most severe form of headache in this class.
- They are far less common than migraine or tension headaches.
- This type of headache begins far more dramatically, and remains quite unique in their course over time.
- As the name suggests, the cluster headache exhibits a clustering of painful attacks over a period of many weeks.
- The pain of a cluster headache peaks in about 5 minutes and may last for an hour. Someone with a this type of headache may get several of them a day for weeks at a time - perhaps months - usually interrupted by a pain-free period of variable length.
- More women than men suffer from migraines, and more men than women suffer from cluster headaches.
- Most people get their first cluster headache at age 25 years, although they may experience their first attacks any time from their teens to their early 50s.
- You can get two types of cluster headaches:
- Episodic: This type is more common. You may have two or three headaches a day for about two months and not experience another headache for a year. The pattern then will repeat itself.
- Chronic: The chronic type behaves similarly but, unfortunately, the person has no period of untreated sustained relief.
What Is a Cluster Headache?
There are two classifications of headaches, and cluster headaches are in a class referred to as primary headaches, and clusters are the most severe form of primary headaches.
- Primary headaches occur on their own. Meaning that there is no other medical disease or problem that is causing the headache. This class of headache is divided into four main groups; migraine, tension, trigeminal autonomic cephalgias (for example, cluster headaches, paroxysmal
hemicranias, and SUNCT), and a miscellaneous group.
- Secondary headaches are caused by an existing illness or disease that affects the brain. The more serious examples include brain tumors, hemorrhagic and ischemic stroke, and head injury.
This kind of headache occurs in clusters, usually at the same time of day or night for several weeks. Clusters of attacks of pain strike one side of the head, for example behind or around one eye. The patient may even experience nausea and a migraine like aura. The intense pain generally peaks around 5 to 10 minutes from when the headache first begins, and then the pain continues at that peak intensity for up to three hours.
Cluster Headache Causes and Triggers
No one knows exactly what causes cluster headaches. As with many other headache syndromes, there are many theories, many of which center on the autonomic or "automatic" nervous system or the brain's hypothalamus. These systems play a role in rhythmic or cyclical functions in your body. The involvement of either system in the syndrome would account for the periodic nature of the headache.
- Many clinical experts believe that cluster and migraine headaches share a common cause that begins in the nerve that carries sensation from the head to the brain (trigeminal nerve) and ends with the blood vessels that surround the brain.
- Other experts believe that the pain arises in the deep vascular channels in the head (for example, the cavernous sinus) and does not involve the trigeminal system.
Other clinical theories and possible triggers include:
Cluster Headache Symptoms and Signs
The pain of cluster headache is its defining and most dramatic symptom (feature). This pain comes on without warning (no forewarning symptoms such as the aura in classic migraine) and may begin as a burning sensation on the side of the patient's nose or deep in the eye.
The pain peaks in just a few minutes. Patients describe the feeling as having an ice pick driven through
their eye. They use words such as "excruciating," "explosive," and "deep." This stabbing eye pain carries with it a rapid electrical-shock like element, which may last for a few seconds, and a deeper element that continues for a half-hour or longer. The pain almost always begins in your eye and always on 1 side of your face. Interestingly, for most patients the pain stays on the same side of the face from cluster to cluster, while in a small minority the pain switches to the opposite side during the next cluster.
In addition to its one-sidedness, other characteristics, symptoms, and signs that separate cluster headaches from other headaches include:
- The headaches commonly come on just after you go to sleep.
- Often the eye on your affected side will tear.
- Your eyelid on the affected side will droop.
- You will experience one-sided nasal stuffiness and runny nose.
- Cluster headaches have seasonal variations. Most attacks occur in January and July, where the days are in turn the shortest and longest.
When Should I Call a Doctor or Other Health Care Professional for Treatment?
Notify your doctor or other medical health care professional in these situations.
- You and the doctor will work out a plan so you will know which types of pain you can deal with safely at home, which require a medical professional, and which require an immediate trip to a hospital's emergency department.
- You should always bear in mind, however, that these headaches can be excruciating, and your doctor always will be there to help you.
- Notify the doctor when you get a severe headache that is not of the same type as the ones you are used to experiencing.
- Call your doctor if you develop a new side effect from the medications you are taking.
- If you have not ever had headaches, or have never seen a doctor for headaches, and have a sudden, severe headache, you should call your doctor or go to a hospital's emergency department.
Seek immediate medical attention or go to a hospital's emergency department under the following circumstances:
- When your current medication does not control the pain and you need immediate relief
- When your pain prevents eating and drinking and you become at significant risk of malnutrition or dehydration
- When you experience profound side effects from your medication such as severe drowsiness, sedation, and nausea and vomiting
- When a doctor advises you to seek evaluation and treatment for any of these problems
- When you have a change in the severity or increased frequency of headaches, or a headache that feels different from any previous headaches
Are There Tests To Diagnose This Type of Headache?
- Your doctor must rule out a variety of other causes of facial pain besides cluster headache to make the diagnosis, including the following unusual forms of headache and facial pain.
- The patient's first experience of a severe explosive headache may be a warning of subarachnoid hemorrhage or bleeding in the head or brain. This is a neurological emergency that needs to be treated immediately by a medical doctor.
- A severe headache also can be a warning of a brain tumor or infection in the head. Both these conditions are rare, but because they are life threatening, the doctor will want to rule these out first.
- Physical examination of your head will help define other possible causes of this painful syndrome. Physical findings in people with cluster headache between attacks are usually normal. During headache attacks, these symptoms may occur:
- Eye tearing
- Pupil of the eye narrows
- Lack of sweating over one-half of the face
- Nasal stuffiness
- Facial and eye redness
- A doctor or other medical professional should complete an initial examination of the patient's nerve response. Doctors reserve more extensive testing, such as a CT scan or MRI, for patients in whom they suspect a more serious condition; for example:
- Skull or brain tumor
- Neurological condition
The doctor or other medical health care professional also may order a lumbar puncture ("spinal tap"). This may help to establish if the cause of the headache is from an infection, or from bleeding in or around the patient's brain.
Cluster Headache Medications for Pain Relief and Prevention
You can treat cluster headache at home under a doctor or other medical health care professionals care. Treatment involves two types of care, preventative and abortive. Many patients require both treatments at the same time.
Preventive treatment: This includes ongoing use of medications proven effective in holding off headaches or limiting their number, even when you are not experiencing headaches. Examples are drugs include:
Abortive treatment: This is designed to stop a headache once it has begun. Prescription medications include:
In addition, many medications used to treat migraine headache (Excedrin Migraine Pain Reliever/Pain Reliever Aid, oxygen, prednisone [Deltasone]) also can be used to treat the condition.
Can Cluster Headaches Be Cured?
Cluster headaches may be ongoing, or they may come and go, and the headache can jump from one type to the other. Many patients who have cluster headache are pain-free for a year or longer, only to have the frustrating cycle of daily headaches begin again.
As is the case with migraine, people with cluster headaches respond to therapies that are widely available and are becoming less expensive. With proper medical treatment and guidance, patients can control cluster headache.
Which types of doctors or other health care professionals diagnose and treat these headaches?
Ideally, the patient will be under the care of a doctor familiar or other health care professional with this type of headache-a neurologist, a pain doctor, or a family doctor with special training with this type of headache.
For More Information on Cluster Headaches
American Academy of Neurology
1080 Montreal Avenue
St. Paul, MN 55116
American Headache Society
19 Mantua Road
Mt. Royal, NJ 08061
National Headache Foundation
428 West St. James Place, 2nd Floor
Chicago, IL 60614-2750
(888) NHF-5552 or (312) 388-6399
National Institute of Neurological Disorders and Stroke
PO Box 5801
Bethesda, MD 20824
American Academy of Neurology American Council for Headache Education
JAMA & Archives Journals
National Headache Foundation
National Institute of Neurological Disorders and Stroke
Worldwide Cluster Headache Support Group