A new device provides noninvasive electrical stimulation of the vagus nerve in the neck to treat episodic cluster headaches. It is call gammaCore and was recently approved by the FDA and will probably be available by prescription in the United States in fall 2017. It is about the size of a cell phone, handheld, applied to the neck at the start of an attack.
Cluster headaches have been called “suicide headaches” because the pain is very intense. They can occur multiple times a day during a cluster. Injectable sumatriptan is almost always very effective within several minutes but may lead to severe adverse effects in people with coronary artery disease or multiple risk factors for that. Also, it is expensive and insurers will not pay for several doses a day. Inhaled oxygen is also effective for most patients. This obviously is less convenient as an oxygen tank is needed and is not covered by Medicare or Medicaid for treatment of cluster headaches. Thus, the gammaCore device is welcome.
There have been 2 “pivotal” trials. Thirty-four percent of patients who use the stimulator experience pain relief in 15 minutes compared 10% who used a sham device. It was effective only for episodic cluster but not for chronic cluster. Patients with episodic cluster, go into remissions whereas those with chronic do not. It is not clear why there was a difference in response as the pathophysiology is the same in both episodic and chronic. Some headache specialists were disappointed that the response rate was only 1/3, “therapeutic gain” is almost 25%. This is considered significant in pain studies
Look for more neuromodulating devices in the future. For cluster, the focus will be on stimulating the sphenopalatine ganglion.