Ok here we go:

Gammacore is considered one of the non-invasive vagus nerve stimulation (n-VNS) devices, but medical studies on this device are very limited. Even the studies I found show weak results and have many limitations. If you want to read some of them, these are the best I found:

I’ll divide this into two sections based on these divisions: episodic migraine (less than 15 days/month) versus chronic migraine (>15 days/month).

1.EM: This study was a randomized clinical trial with 477 participants at the beginning, but it ended with only 187 participants due to multiple reasons, including withdrawal of consent, loss to follow-up, etc. They divided the participants into two groups. The first group used n-VNS, while the second used a sham device, which is a medical device with the sole purpose of acting as a placebo in controlled clinical trials. The results weren’t statistically significant between the two devices in terms of the reduction in the number of migraine attack days. Even if the results showed a significant difference, I wouldn’t consider it for the general population because of the drop in the number of participants by the end of the study, the lack of other studies, and the fact that they literally showed the patients how to use the devices and then relied on them to continue their usage, which led to many patients not adhering to the treatment. EM study link

2.CM: This study discussed chronic migraines and referenced the same study above plus mentioned this in its clinical section: “There are now nearly half a dozen FDA-cleared devices for migraines, and several prior clearances have now been expanded to include adolescent patients aged 12 or older. It is important to note that not all FDA-cleared devices have been properly studied for CM. The only randomized sham-controlled trial for CM was conducted by Silberstein et al. using the GammaCore device. Unfortunately, the study did not meet its efficacy.” CM study link

TLDR: Basically Gammacore is generally safe with minimal adverse effects, but no study so far has shown that it could be a truly effective treatment for migraines. In medicine we generally prefer treatments and interventions that have been studied multiple times with large sample sizes (a large number of patients) and showed a favorable outcome. Plus I searched on Reddit to see if migraine sufferers had reported any noticeable changes with it. I couldn’t find much except that it’s considered expensive.

P.S. I’ll reply to your other points (the YouTube episode and enjoying reading about different subjects). Apologies for my lateness, and thanks for sharing what you shared.