By Ashley Hattle
Cluster headache is the most common type of trigeminal autonomic cephalalgia, affecting one out of 1,000 people. Patients compare the pain to an ice pick or hot poker behind the eye, or a brain freeze that lasts 15 minutes to three hours (sometimes longer) up to eight times a day. Patients with this neurological disorder universally say it’s the worst pain they’ve experienced, even when compared to childbirth, bone fractures, and kidney stones.
Those with cluster headaches often rock back and forth, pace, scream, or hit themselves on the head and prefer loud distractions to a quiet area during attacks. Cluster headaches are linked to circadian rhythms, regulated by the hypothalamus, which monitors the time of day, sleep cycles, and the seasons. People with episodic cluster headaches typically have attacks in the spring and fall months around the equinoxes, and chronic patients go into a “high cycle.”
The diagnosis of episodic clusters requires at least two bouts of attacks that last one week to one year with a remission (pain-free period) of three or more months. Episodic cluster headaches can become chronic and vice versa, often called “chronisodic” by patients. The chronic form is classified as having attacks for at least one year without remission, or a remission that lasts less than three months.
The treatments for cluster headache are unique to the condition, with high-flow oxygen being the most effective and least harmful. Leading neurologists and headache specialists in the field have several recommendations for treatment, and patients have taken it upon themselves to experiment with alternative methods that have led to breakthrough clinical trials. The medications and treatment options are broken down into three categories—acute, transitional, and preventive.
Acute treatments for cluster headache
Cluster headaches occur at the same times each day and require fast-acting intervention to abort the attacks. The pain often peaks within a few minutes of onset, which means medications in pill form won’t work. Opioids are not indicated for cluster headaches and few patients have benefited from them. People with cluster headache often face barriers to treatment, labeled as “drug seekers” as they fight for pain relief.
Proven, effective treatments These acute treatments have been shown to stop cluster attacks within 15 minutes.
- Sumatriptan subcutaneous injection: Patients may be limited to 4-6 pre-filled autoinjectors a month, so some use vials to abort more attacks with less of the drug, using as little as 2-3 mg. The average dosage is 4-6 mg.
High-flow oxygen: Aborting cluster headache with oxygen requires a non-rebreather mask to ensure you’re breathing in 100 percent oxygen, a liter flow rate of at least 12 lpm, and a breathing technique that induces hypoxia. Demand valve systems may offer faster relief and waste less oxygen as the valve shuts off oxygen flow when you stop inhaling. Oxygen may also provide a preventive effect if used at a lower flow rate (5-6 lpm) for 20 minutes before bed or after an attack.
- Noninvasive vagus nerve stimulation: The only device explicitly approved for episodic cluster headaches. The noninvasive handheld piece delivers electrical pulses to the vagus nerve in the neck on the side of the attack in three, two-minute sessions.
Ketamine nasal spray is an emerging abortive option that’s been particularly useful in patients who don’t respond to other treatments. Other medications can offer pain relief within 30 minutes, including zolmitriptan and
sumatriptan nasal sprays. However, some patients have found that drinking a beverage containing caffeine and taurine within a few minutes of onset can stop an attack from progressing.
Transitional treatments for episodic cluster headache
Some interim medications and treatments are used for chronic cluster headaches, but headache doctors try to avoid long-term use because the side effects can be severe. Oral prednisone and greater occipital nerve blocks are used to shorten episodic bouts. A prednisone taper can be very effective at ending a cycle, and occipital nerve blocks reduce the number of attacks and severity of the pain, giving patients relief for up to four weeks at a time.
Patient-led research through patient organization Clusterbusters, Inc., has found that psilocybin mushrooms or lysergic acid diethylamide (LSD) can also work as transitional treatments to knock someone out of an episodic cycle. Low, subhallucinogenic doses can work to end the pain or cut the intensity in half.
Preventive treatments for cluster headache
Prophylactic treatment for cluster headache can be tricky. Verapamil, topiramate, and lithium are often the go-to choices for headache doctors. These medications can have hefty side effects such as cognitive slowing, cardiac arrhythmia, and lithium toxicity. They should be closely monitored by a doctor and discontinued four weeks after an episodic cycle ends or if there is no pain relief or reduction in attacks. Melatonin supplements (10-25 mg) taken before bed can prevent nighttime attacks, and noninvasive vagus nerve stimulation has shown promise as a preventive treatment.
A calcitonin gene-related peptide (CGRP) inhibitor is the first-ever FDA-approved drug for preventing episodic cluster headaches. The drug has helped reduce attack frequency dramatically for episodic patients, but not for chronic cluster headaches.
Psilocybin mushrooms and LSD have been studied for their prophylactic benefits for cluster headaches. Published research from Harvard University and anecdotal evidence have shown that using these substances can help patients skip episodic cycles and bring the pain down to a manageable level for chronic cluster patients.
Cluster headache seems to evolve, meaning what works to abort or prevent attacks for one episodic cycle may not work at all during the next. Patients must have multiple treatments in their toolkit to reach fast and reliable pain relief. •
Ashley Hattle is a medical and fiction writer who has experienced episodic cluster headaches since 2007. She is the award-winning author of Cluster Headaches: A Guide to Surviving One of the Most Painful Conditions Known to Man and a traveling advocate for patients with the neurological disorder with Clusterbusters, Inc.