Vagus Nerve Stimulation to the Ear to Improve Symptoms in Post-COVID-19 and ME/CFS

Transcutaneous auricular vagus nerve stimulation (taVNS) delivered using the CE-certified tVNS® device (tVNS Technologies GmbH). Stimulation parameters include a pulse width of 250-500 μs, frequency of 10-25 Hz, and an individually titrated intensity (typically up to 5 mA). The device operates with a 20-50% duty cycle and is used at home.

Sham stimulation using the same CE-certified tVNS® device. Electrode placement is on the earlobe, which lacks vagus nerve innervation. Stimulation parameters (pulse width, frequency, intensity, duty cycle) mirror those of the active condition, with intensity adjusted to perceptual threshold to mimic the sensation of real stimulation and preserve blinding.