What Is a Cluster Headache?

A cluster headache is characterized by severe pain that is felt along one side of the head. Many patients describe the headache as a drilling, localized sensation that occurs in cyclic clusters. This headache can be brief and last only 15 minutes; however, it can last for up to three hours if left untreated. Sometimes they can reoccur up to eight times a day and linger for weeks before going into remission. Attacks often occur at nighttime and typically awaken an individual one to two hours after he or she falls asleep. Additionally, the occurrence and symptoms of cluster headaches can worsen during certain seasons and at specific times during the day.

A cluster headache diagnosis can be made with the presence of autonomic syndromes such as nasal stuffiness, eyelid drooping, a pupil size that is smaller on the affected part of the head, eye redness and/or tearing and sweating that occurs primarily on the headache side. Other cluster headache symptoms include:

  • Intense pain that is unilateral and occurs in chronic cycles
  • Bouts of pain localized behind, around or above the eye and along the temple
  • Pain that may radiate across the forehead, cheek or jaw and can even affect the teeth and gums
  • Pain that may expand into the ear, neck and shoulder
  • A headache that is always felt on the same side of the head
  • A sense of overwhelming restlessness

Symptoms commonly associated with migraine headaches, such as sensitivity to sound, odors and light, are also known to occur. However, unlike migraines, physical activity and movement does not worsen a cluster headache. Furthermore, while patients with migraines tend to retreat to dark rooms, patients with this condition will generally pace and become restless until their headache is over.


The origin and causes of this headache condition are not well known. Some physicians suggest that nerve and blood vessel abnormalities may be at the root of the problem. Since these headaches tend to occur during certain times of the day or night, hypothalamic abnormalities, which result in sensitivity to the sleep-wake cycle and seasonal changes, may also be factors. A relationship between these headaches and excessive smoking and/or alcohol consumption has also been observed.

Arriving at a Cluster Headache Diagnosis

If you suspect that you might be suffering from this headache condition, you’ll need to visit a cluster headache specialist. He or she will conduct a thorough medical examination that will include evaluating your lifestyle – including your alcohol and smoking habits. Since an increased history of migraine and the occurrence of cluster headache are commonly linked, the physician will also take into account your family medical history. A neurological exam can also reveal symptoms such as eyelid drooping and/or pupillary changes if an attack is occurring or has just taken place.

Based on your medical evaluation, a cluster headache treatment plan will then be implemented. Pharmacological therapy is commonly used, both to stop a current attack and as a preventive treatment. Medications designed to provide instant relief include oxygen, anti-migraine medications such as sumatriptan injections, zolmitriptan nasal spray and certain non-steroidal anti-inflammatory drugs. IV infusions of dihydroergotamine (DHE) are often used to break a headache cycle.

Preventive cluster headache medication includes calcium channel blockers, anti-depressants and anti-seizure drugs. If you experience migraine symptoms such as nausea, vomiting, photophobia and phonophobia, then your physician will most likely recommend anti-seizure medication.

For attacks that typically occur at night, your physician may advise taking melatonin, a natural hormone produced by the pineal gland that could help control your sleep and wake cycles.

Depending on your specific case, your treatment plan could also include occipital nerve blocks and trigger point injections. Psychological intervention may be necessary to eliminate excess alcohol consumption and smoking habits, which could aggravate the severity and frequency of your cluster headaches.

Cluster Headache