Who is a good candidate for vagus nerve stimulation?

Who exactly is a suitable candidate for undergoing vagus nerve stimulation? Is it someone with a specific medical condition, or is it a wider range of individuals? What are the criteria that healthcare professionals consider when determining if someone would benefit from this type of therapy? Are there any potential risks or side effects that patients should be aware of before undergoing the procedure? How does the process of determining eligibility for vagus nerve stimulation typically work?