Cluster headache is among the most severe pains known to mankind. It is characterized by excruciating, debilitating pain lasting from 15 to 180 minutes, or occasionally longer. The pain is usually located around or through one eye or on the temple. The series of cluster headaches usually lasts several weeks to several months, once or twice per year. Clusters may occur every other year, or even less frequently. Several of the following are usually present: lacrimation, nasal congestion, rhinorrhea, conjunctival injection, ptosis, miosis of the pupil, or forehead and facial sweating. Nausea, bradycardia and general perspiration also occur in many patients. Attacks usually recur on the same side of the head. Cluster headaches tend to occur more in spring and fall. There is usually no family history of cluster headache, but occasionally there is such a family history.
Specific Characteristics of Cluster Headaches
Males are afflicted more than females by a 2.5 to 1 ratio. The onset of the clusters is usually between the age of 20 and 45, but there are many cases of clusters in teenagers and occasionally clusters begin in the 50s or 60s and rarely in the 70s. Women tend to have an older age of onset for their cluster headaches than men. Occasionally a brief aura may occur. The prevalence is 0.4% of the population. See Table 1 for a summary of characteristics.
The pain of the cluster attack is extreme and starts very quickly, usually without an aura or a warning. Within minutes, it becomes very severe. Although the pain is usually located about the eye or temple, it may be more intense in the neck or facial areas. Although usually unilateral, the pain changes sides in 10% to 15% of patients—either during a cluster cycle or the next cycle may see pain on the opposite side. The pain itself is excruciating, described in various manners as sharp, stabbing—“like my eye is being pulled out” and occasionally, throbbing.
The length of attack varies, but 45 minutes is the average. Cluster patients usually experience one or two headaches per day, but this may increase to as many as seven per 24 hours or decrease to as little as one or two per week. They usually occur around the same time each day, with the time period 9 pm to 10 am being the most frequent. Approximately half of the patients awaken from sleep with the headaches.
Cluster cycles, except in the chronic variety, usually last 3 to 8 weeks and then stop until the next bout of clusters. The clusters occasionally last as little as several days, or as long as 5 months at which time we begin to think that they may have converted to the chronic cluster type. Ten percent of cluster patients have chronic clusters in which there is no break of at least six months between attacks. One or two bouts of the clusters per year is average for most patients. They may increase in frequency with only several months in between bouts or several years may elapse between attacks. When periodic clusters begin at older ages, the chance of conversion to chronic cluster becomes greater. The natural history of clusters is not known, but the tendency is for the cluster series to stop at a certain age. Many patients “lose” their clusters in the late 30s or 40s, particularly if they have had them for many years.
During the cluster series, over half of the patients are very sensitive to alcohol and most patients will have an attack triggered by ingestion of alcohol. The other ‘headache foods’ are less important, but avoiding MSG, aged cheeses and meats, and chocolate is prudent during the cluster series. MSG, in particular, seems to trigger a more sever cluster in some patients. Cluster patients may have their clusters after stress is over and occasionally excessive cold, heat, or bright light have been associated with the precipitation of a cluster. However, most cluster patients have very little control over the clusters, except with medication.
The typical episodic cluster series builds over one to two weeks and peaks for one to three weeks and then decreases. In the 10% of cluster patients with chronic clusters, periods of peaks and valleys with the headaches also occur but an extended break without any clusters is not present. Chronic clusters are not usually consistent throughout the year but tend to increase in certain seasons. In managing the clusters, we keep in mind the fact that the clusters build and then peak so that I often treat them with somewhat less medication—particularly corticosteroids—in the beginning of a cluster period. The natural history of clusters is unknown. However, it appears as if the more years a patient has them, the more likely they are to abate.
Non-Medication Treatment of Cluster Headache
Other than medication, very little is available for sufferers of cluster headache. The pain is too severe for relaxation methods and some patients state that biofeedback or relaxation may actually precipitate or increase a cluster. However, learning simple deep breathing techniques or relaxation methods does aid some patients in helping to curb the anticipation of the cluster attacks. Much anxiety is generated during the day when the patient knows that nighttime brings intense, excruciating pain.
Icing the area of pain may help, although sometimes heat will be more effective. Some patients let the shower run hot water on their cervical area, or they use a shower water massage apparatus to allow the hot water to run over their cervical or frontal area. Pressing over the temporal area with moderate pressure is occasionally helpful. Cluster patients usually feel better when moving about during an attack. They tend to be active (such as pacing) as opposed to the quiet sought by migraineurs.
Medications For Cluster Headache
For most patients, both abortive and preventive medications are helpful and only in a minority of situations do we simply use abortive medicines. This article will focus only on the abortive medications.