People are experimenting with transauricular vagus nerve stimulation (taVNS), with mixed results, ahead of medical guidelines
Key points you should know:
- In Long COVID and myalgic encephalomyelitis (ME), the vagus nerve may send a persistent “sickness signal,” leaving the body stuck in a state of ongoing immune activation.
- Transauricular vagus nerve stimulation (taVNS) uses a small ear clip to send electrical pulses to this nerve, aiming to calm that response.
- Interest is growing because devices can be relatively affordable and used at home.
- Like many unproven treatments for the heterogeneous disease, responses vary widely — from symptom relief to side effects or significant crashes.
- There are no established guidelines, but some clinical trials are underway. Experts say taVNS should be approached cautiously and is unlikely to work as a stand-alone treatment.
Marci spent £700 ($940 USD) on an electrical device that attaches to the ear after a neurologist suggested it might help nerve pain from fibromyalgia and Long COVID. The 77-year-old retired sociologist (who requested to use only her first name for this story) read the instructions carefully and ran two 10-minute sessions.
“I woke up an hour later doing backward somersaults in my head,” she said. “The vertigo was unbelievable.” The next morning she collapsed. Emergency services brought her to a U.K. hospital, where doctors concluded the device had caused vestibular neuritis, an inflammation of the nerve responsible for balance.
The company refunded Marci’s money. She has not tried the device again.
This type of electrical stimulation is not new. Targeting the vagus nerve, an important connector between the brain and other organs, is already approved by the U.S. Food and Drug Administration (FDA) as a treatment for epilepsy, depression, and, more recently, rheumatoid arthritis. These methods typically apply stimulation to the neck through implants or external electrodes.
Now a different approach is gaining attention among people with Long COVID and myalgic encephalomyelitis (ME): transauricular vagus nerve stimulation (taVNS). In taVNS, an ear clip delivers electrical pulses through the skin to reach a small branch of the vagus nerve in the outer ear, rather than stimulating the nerve via the neck.
The setup can be simple. Standard transcutaneous electrical nerve stimulation (TENS) machines, sold for muscle pain, cost around $60 to $70. Specialized taVNS devices, on the other hand, can cost several hundred dollars.
Most people trying these devices for Long COVID or ME rely on protocols shared in online communities, or on manufacturer instructions that may not account for individual differences. Small changes in electrode placement or a person’s baseline on a given day can affect how the stimulation feels. And, like many treatments for a heterogeneous disease like Long COVID, results have been mixed. Some have reported improvements in fatigue, breathing, and cognitive dysfunction. Still, it’s no silver bullet, and others have experienced severe crashes.
Several clinical trials are underway for taVNS as a treatment for Long COVID, but clear guidelines are not yet available. Michael VanElzakker, a neuroscientist at Massachusetts General Hospital and Harvard Medical School, said research is moving toward more precise options, which are needed for these complex diseases.
When the sickness signal does not switch off
The idea behind ear stimulation is rooted in how the body detects illness. The vagus nerve acts as a major communication pathway between the brain and internal organs, helping to signal to the brain when the body is sick.
When the immune system detects a threat, it releases molecules called cytokines that trigger inflammation and signal that the body is under attack. The vagus nerve picks up those signals and relays them to the brain, producing what researchers call “sickness behavior,” including fatigue, loss of appetite, and social withdrawal — responses that help conserve energy and promote recovery.
VanElzakker proposed in 2013 that many chronic symptoms in ME could reflect a sickness response that never shuts off following infection of the vagus nerve itself.
Earlier studies in animals showed how central the vagus nerve is to this signaling process. When researchers exposed rodents to immune triggers, they stopped socializing and lost interest in food. But when the vagus nerve was cut, that behavior disappeared, even though immune signals in the body remained unchanged. “The brain doesn’t find out that the body is sick,” VanElzakker said.
More recent evidence suggests that this pathway may also be affected in people with Long COVID. One proposed mechanism involves direct disruption of the vagus nerve’s anti-inflammatory signaling.
Several studies have documented changes along this pathway. A 2023 postmortem study found traces of SARS-CoV-2 in vagus nerve tissue and near the brain stem, where these signals are processed. Other research has linked Long COVID to structural changes in the vagus nerve alongside gut and respiratory dysfunction.
The virus’s spike protein may also interfere with the nerve’s role in controlling inflammation, although this has so far been shown only in laboratory settings. Another possibility is an autoimmune process, which has also been linked to ME following infections other than SARS-CoV-2.
Richard Crevenna, a rehabilitation specialist at the Medical University of Vienna, describes this as autonomic imbalance. He hypothesizes that many people with Long COVID are stuck in a state called “sympathicotonia,” where the body remains locked in a chronic stress response.
TaVNS is an attempt to manually override that alarm. Finding the right settings, however, is not straightforward. Frequency, pulse width, intensity, duration, and time of day can all influence how the nervous system responds.
Trying it at home
Despite the uncertainty, many people with Long COVID and ME have started experimenting with taVNS at home.
Vanessa (who requested to use only her first name for this story), a 45-year-old former accountant from Mexico, tried taVNS to help with heart rhythm problems and tachycardia caused by a SARS-CoV-2 infection in 2022. Now living in the Netherlands, she spent €600 ($700 USD) on a high-end device.
Her first session caused intense burning sensations. “It felt like my skin was on fire,” she said. She later tried a TENS unit. That attempt triggered a two-week crash. “These things stress my nervous system more than relaxing it.”
Others have had more positive experiences.
Vid Nerad Rožej, a 23-year-old physiotherapy student in Slovenia, began using an €70 ($82 USD) TENS setup after developing Long COVID in 2022. Before trying stimulation, Rožej said he felt like he was “almost suffocating” about 75% of the time. The stimulation has helped reduce his breathing symptoms, though only while he continues using it.
Troy Pearse, a 60-year-old retired software engineer in the U.S., took a more structured approach to the stimulation. After a SARS-CoV-2 infection in 2020, he developed autonomic dysfunction and a brain injury. To guide his sessions, he tracks his heart rate variability (HRV) using a wearable device.
“The TENS unit works very well and is very affordable,” he said, though he is careful about combining taVNS with other treatments to avoid overstimulation.
These anecdotes match data from a 2024 international survey conducted by Physios for ME and collaborators.
In that survey, 56% of 116 people with ME rated taVNS as beneficial, with reported improvements in post-exertional malaise (PEM), pain, gut problems, and mental health. At the same time, 6% said their symptoms worsened. One person reported a severe crash lasting months. Only 8.6% had received guidance in using the devices from a healthcare provider.
For Karen Leslie, co-founder of Physios for ME and researcher at the University of Liverpool, the mixed results reflect how much remains unknown. She described taVNS as a “muddy intervention,” with effects that are difficult to predict.
She described taVNS as a “muddy intervention,” with effects that are difficult to predict.
Karen Leslie, co-founder of Physios for ME
What the research shows so far
Clinical studies are beginning to explore how taVNS might be used more safely.
Crevenna led a 2025 pilot study testing whether 36 women with Long COVID could feasibly use a standard TENS device at home. While the study did find symptom improvements, it was too small to detect frequency differences. A similar trial from Germany involving 45 participants also found no significant difference between active stimulation, subthreshold stimulation, and placebo.
Leslie recently completed a feasibility trial focused on people with ME. Her team enrolled 40 participants and compared 12 weeks of active stimulation with a placebo. Testing took place in participants’ homes and the placebo group was switched to active stimulation at week 12. Six months later, everyone was interviewed again.
“What we’re looking at is, is it safe to study with people with ME, and if so, what’s the best way of doing it?” Leslie said. Results are not yet available.
Several other trials are ongoing.
At the Icahn School of Medicine at Mount Sinai in New York, a team led by Benjamin Natelson is running a randomized study in people with Long COVID who also meet ME criteria. The trial is currently recruiting, and compares two stimulation approaches over six weeks without clinic visits.
In Europe, the STIMPACT study, led by André Schulz at the University of Luxembourg, is testing a crossover design for people with Long COVID or ME with two four-week intervention phases. Data collection is expected to continue through 2026.
Part of what makes all these trial results difficult to interpret is that the body itself is constantly changing. Biomarkers such as cytokines can fluctuate with sleep, diet, or time of day, VanElzakker said. Leslie added that even HRV lacks a unified measurement protocol, making it hard to distinguish treatment effects from normal variation.
That uncertainty is one reason researchers are also trying to better understand the underlying biology. VanElzakker, who co-founded the PolyBio Research Foundation, is investigating whether the vagus nerve is more sensitive in people with Long COVID using a device compatible with functional magnetic resonance imaging (fMRI) to compare brain responses. The findings are not yet available but could help explain why stimulation affects people so differently.
Considerations for people thinking about trying taVNS
For those considering taVNS, both researchers and people who have tried it emphasize caution.
VanElzakker recommends starting at the lowest possible setting and building up slowly. He also pointed to a common cause of headaches from taVNS: a poor electrical signal caused by ear wax or skin oils. “Scrub your ear more than you think [you need to],” he said. Crevenna emphasized that anyone with significant symptoms, particularly autonomic instability or heart irregularities, should be evaluated by a physician first.
Leslie pointed to the wide variation in device costs and the way some companies market them. Some marketing of the devices promises to “rewire the nervous system” or deliver “lasting calm,” claims that are not supported by strong evidence. That kind of language is worth treating with skepticism.
People who tried the devices for Long COVID and spoke to The Sick Times suggest starting with a cheaper device to see whether anything changes before investing more money. “Start with a regular TENS device,” Rožej said, “instead of spending a hundred euros immediately.” Others stress the importance of introducing only one new treatment at a time, so that any effects can be traced more clearly.
Whatever the trials show, researchers agree that taVNS may address one piece of a much larger puzzle. Long COVID and ME disrupt the nervous system, the immune system, and metabolic function all at once, and no single existing intervention targets all of that. “Human beings make these divisions: nervous system, immune system, gut,” VanElzakker said. “Nature doesn’t think like that.”
For patients, that complexity often translates into trial and error. As Marci put it, “This machine is not for everybody.”
For patients, that complexity often translates into trial and error. As Marci put it, “This machine is not for everybody.”
Corina Maller is a science and medical writer based in Europe with a focus on chronic disease, nutrition, and the gut microbiome. She creates content for medical organizations and therapy platforms and shares her personal research and experience through her blog, GUTYOU.
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