Hi, Vagus nerve supplies in many major organs like heart, lungs, stomach, palate, esophagus etc. Therefore, if vague nerve damage, this can cause bradycardia( decreases heart rate) ,arrhythmia, voice changes, difficulty in swallowing, gag reflex, constipation and incontinence but its damage does not cause dehydration. However, vagus nerve effect can be amplified by dehydration (though dehydration may originate due to any gastrointestinal illness through vomiting or diarrhea etc.). In addition, vagus nerve stimulation by dehydration can lead to decrease in heart rate/pressure and then fainting. If this damage is confirmed by a neurologist, then vagus nerve stimulation and blocking therapy can be two forms of treatments available for vagus nerve damage and they can be utilized as per the requirement of the case. Surgical option (vagotomy) can be kept reserved in severe cases. Hope this helps.
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