Influence of vagus nerve stimulation on histamine-induced itching

To investigate whether vagus nerve stimulation (VNS) reduces pruritus in humans.Recently, it has been shown that VNS has antinociceptive and antidepressant effects in humans.Eleven patients were investigated before (baseline) and during chronic VNS treatment. The experiments were performed at two different stimulation intensities: 2 to 5 days after implantation at a low stimulation intensity (mean intensity 0.7 +/- 0.2 mA, second session) and after 8 to 14 weeks of VNS therapy (mean intensity 1.4 +/- 0.3 mA, third session). Twelve healthy age- and sex-matched subjects were investigated using the same experimental protocol. Itch was induced by histamine-iontophoresis and quantified on a visu…