Are there any side effects to using the VNS?

The only effect I’ve seen in children is that VNS can drop brain blood pressure levels on rare occasions and lead to a slight increase in hyperactivity and maybe some anxiety. Shifting the VNS to bedtime when the child is lying flat and will have near-normal brain pressure (lying flat eliminates the stress of gravity) seems to alleviate this issue. After a few months, when the blood pressure regulation has improved, the VNS can be used in the daytime without any apparent side effects.