Combating Cluster Headaches on Every Front
A cluster headache is a relatively rare type of headache that affects less than 0.5% of the population. It’s called a cluster headache because it tends to occur daily for weeks to months at a time and then disappear for a month or more.
Unlike migraines, cluster headaches are more common in men than women, although the proportion of women diagnosed with cluster headache has risen over the past 20 years. The headaches can start at any age and often begin in a person’s 20s or 30s.
Specialists at UT Southwestern offer compassionate, personalized care for people with cluster headaches, from making an accurate diagnosis to creating a comprehensive approach for treating this confounding condition.
Symptoms and Triggers
Cluster headaches are often seasonal. The attacks often awaken people from sleep at the same time each night. Most people experience more than one attack each day, often in the late afternoon or evening. About 10 to 20% of patients have chronic cluster headaches that never go away or have remission periods of less than one month.
Cluster headache pain comes on quickly and usually without a warning – an attack can last from 15 minutes to three hours. There might be other vague symptoms prior to an attack, such as mood changes, yawning, or food cravings.
Cluster headaches are excruciating – they are sometimes called “suicide headaches” – and patients often describe the pain as boring, stabbing, knifelike, or burning.
The pain is located around the eyes and temple but can also extend to other areas such as the:
- Jaw
- Cheek
- Teeth
- Nose
- Side of the head
In most patients, the attacks occur on the same side of the head during a cluster period.
Most patients experience agitation or become restless during a cluster headache and prefer to pace, rock back and forth, go outdoors, or strike their head to distract themselves from the pain. Others prefer to sit still, but it is uncommon to want to lie down during an attack.
Cluster headaches are often accompanied by involuntary symptoms, often on the same side of the head as the pain. These symptoms are caused by activity of specific nerves in the brain and head. They include:
- Droopy eyelid
- Small pupil
- Eyelid swelling
- Tearing
- Bloodshot eye
- Stuffy or runny nose
- Flushing
- Sweating
Some patients with cluster headaches also have symptoms that are more typical of migraine, such as:
- Aura
- Sensitivity to light or noise
- Nausea
- Vomiting
Most patients with cluster headaches are smokers or ex-smokers. Common triggers for cluster headaches include:
- Alcohol
- Odors such as those from solvents or perfume
- Sleep
- Smoking
- Certain foods
Diagnosis
To diagnose cluster headaches, UT Southwestern physicians will conduct a thorough evaluation of a patient’s medical history and perform a neurological examination.
Brain imaging is recommended for all patients with cluster headaches. Rarely, brain abnormalities (such as a tumor of the pituitary gland) can cause headaches that are very similar to cluster headaches.
Treatment Options
Cluster headaches can be a lifelong condition in most patients, although remission periods tend to get longer with age. To reduce the severity and the frequency of these headaches, three aspects of treatment are generally all started at the same time.
Treating the Acute Attack
Because cluster headaches are relatively brief, oral medication is usually ineffective. Immediate treatment options might include:
- Oxygen: 100% oxygen through a non-rebreather face mask at 7 to 12 liters per minute relieves the headache in more than half of patients. The oxygen should be used for 15 to 20 minutes. However, about 25% of patients have incomplete relief, experiencing only a delay in their headache after using oxygen.
- Triptans: Injectable sumatriptan, sumatriptan nasal spray, and zolmitriptan nasal spray are often effective. Because cluster headaches occur multiple times a day, these treatments are expensive and often not covered by insurers in the quantity needed. Frequent use can lead to “rebound” headaches that are difficult to treat.
- Ergots: Dihydroergotamine (DHE) injections and intravenous DHE are effective treatments. DHE nasal spray might also be considered. Other ergots are useful.
- Lidocaine: A 10% solution (a local anesthetic) administered into the nose on a cotton swab or by nasal spray is effective in many patients.
Stopping the Cluster Period
In addition to treating the current attack, steroids might be prescribed to stop the cluster period, sometimes in combination with injection of an anesthetic into the greater occipital nerve.
Steroid treatment is usually effective within days. Common side effects of steroid treatment include:
- Insomnia
- Increased appetite
- Stomach pain
Long-term side effects include ulcer, osteoporosis, fracture, diabetes, weight gain, glaucoma, and easy bruising. Because of these side effects, steroids cannot be used indefinitely – preventive treatment is also needed.
Preventing Headaches Over the Long Term
Medications are often prescribed to prevent long-term recurrence. Possible medications include:
- Verapamil: Perhaps the most effective long-term preventive treatment for cluster headaches. The dose needed for cluster headaches is substantially higher than the dose used for treating blood pressure (up to 960 mg daily). Constipation is a common side effect, although the drug is usually very well tolerated in people with cluster headaches. Because verapamil occasionally causes abnormal electrical conduction in the heart (prolonged QT interval), intermittent electrocardiogram (EKG) monitoring is performed when using high doses.
- Lithium: Successfully used for many years as a preventive treatment for cluster headaches. A dose of 600 to 1,200 mg daily generally works within days. Short-term side effects include weakness, nausea, tremor, and slurred speech. Lithium blood levels, kidney function, and thyroid function must be monitored during treatment.
- Topiramate: Approved by the U.S. Food and Drug Administration (FDA) for migraine prevention and also useful in cluster headaches. It is started at a low dose and increased as tolerated; the effect is seen in one to four weeks. Common side effects are drowsiness, weight loss, memory problems, and tingling. Kidney stones, the sudden onset of glaucoma, and allergy are rare but serious side effects.
- Gabapentin: Administered in doses of 900 mg daily. This medication can be effective as quickly as one week after starting treatment. Drowsiness and dizziness are the most common side effects.
Several studies of valproate have shown mixed results, but it seems to be effective. Weight gain, tremor, hair loss, and mood change are common side effects, and the drug cannot be used during pregnancy.
Although methysergide can be very effective, this medication is no longer available. Testosterone replacement in men with low testosterone levels might improve the headaches.
Botulinum toxin injections have not been studied, but there are reports of their usefulness when oral medications fail.
Surgical Options
If cluster headaches persist despite medical treatment, surgical options might be considered. Surgical treatment of cluster headaches might include:
- Occipital nerve stimulation: A lead is implanted over the occipital nerve in the back of the head/neck, which is connected to a battery-powered stimulator. The intensity of attacks seems to decrease sooner than the frequency, and improvement occurs in days to weeks.
- Hypothalamic stimulation: The hypothalamus is deep within the brain and regulates hunger, thirst, and circadian rhythms. Several studies using functional MRI and PET scans show that the hypothalamus is activated in patients with cluster headaches. Stimulation in this part of the brain counteracts the hyperactivity to reduce headache intensity and frequency. This procedure has significant risk and is not done at most medical centers.
- Destructive surgery: A last resort, this procedure has serious risk.