There are three aspects of treatment for cluster headaches and they are generally all started at the same time.
Treatment of the Acute Attack
Since cluster headaches are relatively brief, the acute treatment must act rapidly. Therefore, oral medication is usually ineffective.
Treatment options include:
- 100 percent oxygen through a non-rebreather face mask at 7-12 liters per minute relieves the headache in over half of patients. The oxygen should be used for 15-20 minutes. However, about 25 percent of patients have incomplete relief with a delay in their headache after using oxygen.
- Injectable sumatriptan, sumatriptan nasal spray, and zolmitriptan nasal spray are often effective. Since 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.
- Dihydroergotamine (DHE) injections and intravenous DHE are effective treatments. DHE nasal spray may also be considered. Other ergots are useful.
- 10 percent 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
Steroids such as prednisone, prednisolone, and dexamethasone usually stop the headaches within days. They are started at a moderate to high dose (prednisone 40-80 mg daily) and the dose is reduced every few days. Sometimes the headaches return as the dose is tapered, requiring an increase in dosage with retapering.
Common side effects of steroids are insomnia, increased appetite, and stomach pain. Long-term side effects include ulcer, osteoporosis, fracture, diabetes, weight gain, glaucoma, and easy bruising.
Because of the side effects, steroids cannot be used indefinitely – preventive treatment is also needed. Greater occipital nerve injection of a long-acting local anesthetic, combined with a steroid, sometimes breaks the cycle.
Verapamil is perhaps the most effective long-term preventive treatment for cluster headaches. The dose needed for cluster headache 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 Q-T interval), intermittent EKG monitoring is performed when using high doses.
Lithium (600-1,200 mg daily) has been successfully used for many years as a preventive treatment for cluster headache. It 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 is FDA-approved for migraine prevention and is also useful in cluster headache. 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, may be effective as quickly as one week after starting treatment. Drowsiness and dizziness are the most common side effects.
Several studies of valproate showed mixed results but it seems to be effective. Weight gain, tremor, hair loss, and mood change are common side effects and the the drug may not be used during pregnancy.
Although methysergide can be very effective, this medication is no longer available. Testosterone replacement in men with low testosterone levels may improve the headaches.
Botulinum toxin injections have not been studied, but there are reports of their usefulness when oral medications fail.
When the headaches persist despite medical treatment, surgical options are considered.
Occipital nerve stimulation is often effective. 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 is a new approach to cluster headache treatment. The hypothalamus is located deep within the brain and is the part of the brain that regulates hunger, thirst, and circadian rhythms. Several studies using functional MRI and PET scans show that it is activated in patients with cluster headache. This procedure has significant risk and is not done at most medical centers.
Destructive surgery is a last resort and has serious risk.