Positives

• One patient reported using a TENS unit nightly with vagus nerve placement and finding it very helpful for sleep quality, especially when paired with breathing exercises Health Rising.
  
  
• Patients using a TENS 7000 with ear clips for tVNS reported improvements in taste and tolerance of foods after about 4 weeks PMC.
  
  

Negatives

• One patient reported trying a TENS device on the earlobes for about 3 weeks without noticing any change, and described painful vibrations due to coexisting fibromyalgia Health Rising.
  
  
• Patients are cautioned that improvised settings on a generic TENS device can carry cardiac risks, and several patients describe inconsistent symptom response Scientificamerican.
  
  

Hurdles & Side Effects

• Generic TENS units run roughly $30-$80 plus optional ear clip electrodes, but no protocol is standardized for Long COVID and patients must self-titrate placement and intensity Health Rising.
  
  
• Daily 30-60 minute sessions plus the technique difficulty of correctly locating the auricular branch of the vagus nerve discourage many patients PMC.