Yes, please refer to the user manual or instruction for use of each individual device to learn more about the specific contraindications associated with your device of choice.

VNS effects can be antagonized by intrathecal naloxone or methysergide/phentolamine combined, suggesting the involvement of descending serotonergic and noradrenergic systems, as well as opioid receptors (Yuan and Silberstein, 2016c).

Increased parasympathetic outflow to the lungs when nonselective VNS is applied may result in bronchoconstriction, increased mucus secretion. enhanced local pulmonary inflammatory activity, potentially outweighing the beneficial systemic anti-inflammatory action of VNS (Mastitskaya et al., 2021).

One of the main contraindications  to VNS therapy is the effect on baseline cardiac conduction disorders. There is the potential for efferent conduction through the vagus nerve, especially when the device is placed on the right-hand side of the neck, and may worsen cardiac conduction abnormalities. VNS therapy is also contraindicated in patients who have undergone bilateral or left cervical vagotomy procedures (Ohemeng and Parham, 2021).