Tragus Nerve Stimulation Attenuates Postural Orthostatic Tachycardia Syndrome in Post COVID-19 Infection, 2025, Zhuo Wang et al

ABSTRACT
Background
Postural orthostatic tachycardia syndrome (POTS) is characterized by symptoms of orthostatic intolerance and is frequently observed in post-COVID conditions.

Objectives
We conducted controlled, prospective, and randomized clinical trials to explore the potential therapeutic benefits of low-level tragus stimulation (LL-TS) in patients with POTS following COVID-19 infection.

Methods
This study enrolled 57 participants with confirmed post-acute COVID-19 who had been diagnosed with POTS. The ear clip was attached to the right tragus of the patients for stimulation (20 Hz with a 1-ms duration) or sham stimulation. They were divided into two groups: the sham LL-TS group (sham stimulation, n = 26) and the LL-TS group (stimulation for 1 month, n = 31). LL-TS was performed 1 h twice daily for 1 month. Postural tachycardia was evaluated at baseline, 1-month visit, and 1-year visit. Heart rate variability (HRV) and plasma neuropeptide Y (NPY) were evaluated at respective time points.

Results
The mean age of participants was 31.9 ± 7.2 years (61.4% female). LL-TS significantly attenuated the increase in heart rate from supine to a 10-min stand, as well as the average and maximum heart rates after 1 month of treatment. LL-TS also significantly reduced NPY levels. In addition, LL-TS significantly increased the high frequency (HF), but decreased the low frequency (LF) and LF/HF ratio during the postural test (all p < 0.01). These effects persisted during the 1-year follow-up.

Conclusion
LL-TS may be a promising therapeutic approach for attenuating autonomic imbalance in patients with POTS following COVID-19 infection.
LINK

 

Grey = treatment group

 

They did not measure symptoms related to POT, which is a shame.

It’s surprising that the changes lasted for so long.

 

It might be that this study stumbled upon a sweet spot of 20 Hz with a 1-ms duration? I have not read the VNS thread yet.

 

I can only speculate, but I can imagine that the right frequency could be tied to the physical properties of the nervous system? I’m not sure if those are different in different people.

 

Looks like this study has also showed similar results:

Edit: posted elsewhere

https://www.sciencedirect.com/science/article/pii/S2405500X2300806X

 

Discussed here:
https://www.s4me.info/threads/nonin...hycardia-syndrome-2023-stavrakis-et-al.36968/

 

I’m not sure if the blinding was necessarily well done.

Because when my VNS is on I can feel a slight electrical tingling on my ear. I’m willing to bet since the “sham” was sending no current the controls didn’t feel that.

I really feel like they should be comparing frequencies instead of doing an impossible blinding.

 

According to other patients, the feeling depends on the Amp - you don’t feel it if it’s low enough. I can’t find the Amp figures in this study, though.

 

I honestly know nothing about electronics so Amp Frequency Volt make no sense to me.

I was sick with my COVID infection that eventually got me here when we were covering that in school haha. (So I’ll trust your judgement).

 

@Yann04 Here’s a brief summary in case anyone are interested.

Amp and Volt are two different measures of how much electricity that’s flowing through the cable. If you multiply them with eachother, you get Watts.

Higher Amp is like a wider water pipe, but the same water pressure. Higher Volt is like more water pressure, but the same size pipe. Higher Watts just means more water through the pipe in total, irrespective of how it was achieved.

Ohm is resistance, i.e. how ‘easy’ or ‘hard’ it is for the electricity to flow through the cable.

Hz (frequency) says how often the current switches from positive to negative. 60 hz = 60 switches in one second. This is only relevant for AC (alternate current). DC (direct current) doesn’t switch.