The purpose of this study is to investigate how the electrical stimulation of a nerve in the
skin of the earlobe (transcutaneous vagal nerve stimulation), alone or in combination with
two medications (galantamine and pyridostigmine), affects the way the autonomic (involuntary)
nervous system controls heart rhythm, symptoms on standing, and inflammatory markers in
female patients with postural tachycardia syndrome (POTS). The study consists of 2 parts: a
screening (1-2 study days), and 3 testing days. The study will take 5 days total and about 16
participants will be screened for the study. The investigators estimate 13 will be eligible
to participate in all of the study days.