Search “stellate ganglion block for Long COVID” and you will find two kinds of pages. Clinics saying it works, and skeptics calling it unproven. Both are partly right, but neither tells you the whole story.
So here is the actual evidence, the supportive studies and the inconvenient ones, laid out so you can decide for yourself.
The summary: Several studies show Long COVID patients may improve after a stellate ganglion block (or SGB), especially those whose symptoms run through the autonomic nervous system. But every one of those Long COVID studies lacked a control group, the single randomized trial in this space was negative, and durability is inconsistent. The treatment has a real signal and a thin evidence base at the same time.
The studies supporting SGB for Long COVID
The most cited study is a 2023 retrospective cohort in Cureus by Pearson and colleagues. Across 41 patients, 86% reported improvement in at least one Long COVID symptom, with strong responses in fatigue, joint pain, headache, brain fog and palpitations. This is the source of the “86%” figure you see. It is a real published number, but it describes 41 self-referred patients with no comparison group, and the authors later disclosed in a published correction that they were affiliated with the clinic where the procedures were done.
That does not erase the result, but it is the kind of detail you should know.
The earliest signal came from a 2022 case series by Liu and Duricka in the Journal of Neuroimmunology. It is foundational, and it is also just two patients, so it carries historical weight rather than statistical weight. A 2022 case report by Khan and colleagues in Cureus added another documented responder.
Then, in 2026, a systematic review in Current Pain and Headache Reports pulled together seven studies. It found symptom improvement across all of them, with response rates ranging widely, near 56% in the larger studies and as high as 100% in the smallest, and it specifically concluded the patients most likely to benefit are those with prominent autonomic dysfunction. That last point matters, and we will come back to it.
The study complicating the picture
In 2025, a research group at Brigham and Women’s Hospital published the most cautious dataset yet, 52 Long COVID patients treated with SGB. About 56% reported at least some improvement, but only around 14% saw relief clearly persist, and patients averaged roughly three injections. Brain fog, fatigue, dizziness and headache improved the most. Post-exertional malaise, the crash after activity, barely moved.
This is the study a good clinic shows you, not the one it hides. It says the treatment helps a majority at least temporarily, helps a minority durably, does little for PEM, and usually takes more than one session. That is a more useful picture than “86%” on its own.
The one randomized trial, and what it found
In 2025, a randomized, sham-controlled trial tested SGB specifically for COVID-induced parosmia, the distorted-smell symptom. It found SGB was not superior to placebo and concluded it should not be recommended for parosmia. It was small and it studied one symptom, but it is the highest-quality study design in this entire space, and it was negative.
That does not erase the autonomic findings, built on different symptoms. When the only randomized trial in a field comes back null, it is a signal that some of the open-label improvement seen elsewhere could be placebo, natural recovery or regression to the mean.
Honesty here is how you tell a careful clinic from a marketing page.
What the strongest evidence is actually for
SGB does have strong randomized evidence behind it, just not for Long COVID. A sham-controlled trial in JAMA Psychiatry, run in active-duty service members, found two stellate ganglion blocks meaningfully reduced PTSD symptoms compared with a sham procedure. That trial is the reason SGB is taken seriously as an autonomic intervention at all.
So the fair way to state it is this. The mechanism is well established and the procedure has proven it can change autonomic and stress physiology in a rigorous trial.
The Long COVID application is a reasonable extension of this mechanism, supported by promising but uncontrolled studies, and it is still waiting for its own randomized trial.
How to read all of this together
Put the studies side by side and a consistent pattern appears. SGB helps a meaningful share of Long COVID patients, the responders are disproportionately those with autonomic dysfunction such as POTS and dysregulated heart rate, the gains are sometimes durable and sometimes temporary, and the proof is suggestive rather than definitive.
The treatment is neither a miracle nor a scam: a plausible, mechanism-based option with a real probability of helping the right patient.
The single biggest predictor of a good result is whether your symptoms are driven by a stuck sympathetic nervous system, not the clinic or the technique. That is a question worth answering before you book an appointment.
Where SGB fits among other Long COVID approaches
A stellate ganglion block is not a standalone cure, and it does not address every form of Long COVID.
The autonomic nervous system is one of several drivers of post-COVID illness, alongside gut dysbiosis, mitochondrial dysfunction, mast cell activation and endothelial dysfunction with microclots. SGB targets the autonomic arm. If your illness is running mostly through one of the others, a block may not reach it.
That is why it works best inside a plan, not as a one-off. For autonomic symptoms, it pairs naturally with vagus nerve stimulation and with the standard POTS toolkit of fluids, salt, compression, graded exercise and rate-control medications. For the non-autonomic mechanisms, the answer may be a different treatment entirely. The point of a proper evaluation is to sort out which mechanisms are driving your case so the treatment matches the problem. You can read how that assessment works in the four-step process.
Who should be cautious
Be cautious if your symptoms are clearly not autonomic, if you are expecting a permanent one-shot cure, or if a provider promises certainty that the evidence does not support. Tell any provider about blood thinners, which may need to be paused before the procedure.
And ask hard questions about technique and experience, because results depend on both.
The realistic expectation is, if autonomic dysfunction is driving your Long COVID, a stellate ganglion block has a fair chance of helping, possibly more than once, and it carries a low risk in experienced hands. That is a reasonable bet for the right patient. It is not a guarantee, and no careful clinic will frame it as one.
See if SGB is right for you
The studies agree on one thing and the patients helped are those whose symptoms come from a dysregulated autonomic nervous system. Finding out whether that is you is the first step.
Request a consultation with Dr. Groysman
Read more on the main stellate ganglion block page, or about SGB for POTS and what a successful block looks like, or see the Reddit questions, answered.
References
- Pearson L, Maina A, Compratt T, et al. Stellate Ganglion Block Relieves Long COVID-19 Symptoms in 86% of Patients: A Retrospective Cohort Study. Cureus. 2023. PMID 37711269.
- Liu LD, Duricka DL. Stellate ganglion block reduces symptoms of Long COVID: A case series. J Neuroimmunol. 2022. PMID 34922127.
- Khan MH, Kirkpatrick KP, Deng Y, Shah KB. Stellate Ganglion Block for Long COVID Symptom Management: A Case Report. Cureus. 2022. PMID 36628048.
- Chiang MC, Satko KM, Shin C, et al. Stellate Ganglion Block for the Management of Long COVID Symptoms: A Retrospective Cohort Study. Cureus. 2025. PMC12374758. (The Brigham and Women’s Hospital cohort.)
- Peddireddy S, VanWingerden N, Patel P, Howard G, Berger J. Stellate Ganglion Block in the Treatment of Long COVID: A Systematic Review. Current Pain and Headache Reports. 2026;30(1):44. PMC13076556.
- Farrell NF, Crock LW, Islam A, et al. Stellate Ganglion Block for the Treatment of COVID-19-Induced Parosmia: A Randomized Clinical Trial. JAMA Otolaryngology Head & Neck Surgery. 2025. PMID 40504522.
- Rae Olmsted KL, et al. Effect of Stellate Ganglion Block Treatment on Posttraumatic Stress Disorder Symptoms: A Randomized Clinical Trial. JAMA Psychiatry. 2020. PMID 31693083.