04/17/2026
Claude AI is a next-generation AI assistant developed by Anthropic, designed to be safe, honest, and helpful.
When we asked Claude AI about more information regarding the SGB for Long COVID, this is how they responded.
*Disclaimer- lengthy, but interesting read, especially since they mention how treating Long COVID with SGB was in fact pioneered by Dr. Liu!!
Stellate ganglion block (SGB) for long COVID is a fascinating and still-emerging area. Let me search for the latest on this. Here's a thorough rundown on this topic.
What the procedure is and the theory behind it:
The stellate ganglion is a bundle of sympathetic nerves in the neck, formed by the fusion of the inferior cervical and first thoracic ganglia (in about 80% of the population). SGB involves injecting local anesthetic near the stellate ganglion under ultrasound guidance, which blocks activity of the entire cervical sympathetic chain. A successful block produces Horner's syndrome—ipsilateral ptosis, miosis, anhidrosis, and facial flushing.
The rationale for long COVID rests on the dysautonomia hypothesis. Many long COVID symptoms—fatigue, orthostatic intolerance, brain fog, anosmia, and taste disturbance—resemble "sickness behavior," the autonomic nervous system's response to pro-inflammatory cytokines. The idea is that COVID triggers a persistent sympathetic/parasympathetic imbalance, and blocking cervical sympathetic chain activity with local anesthetic allows the regional autonomic nervous system to "reboot." There are also theories that SGB modulates the immune system through the sympathetic-immune axis and that it increases cerebral blood flow, which may improve neurological symptoms.
Who pioneered the approach:
The story has two chapters. SGB itself dates back to at least 1926 as a treatment for chronic pain, and it has been a standard pain management procedure for nearly a century.
The modern innovator is Dr. Eugene Lipov, a Chicago-based anesthesiologist. In 2006, he became the first physician to use SGB to treat PTSD, and his research earned him an invitation to testify before the U.S. House Committee on Veterans' Affairs in 2010. He developed an advanced protocol called the "Dual Sympathetic Reset" (DSR), involving bilateral injections. He is now Chief Medical Officer at Stella Center, a clinic network that has commercialized this treatment.
The specific application to long COVID was pioneered by Dr. Luke Liu, an interventional pain specialist at Neuroversion Inc. in Anchorage, Alaska (and a Stella-certified provider). In December 2021, Liu published the first case report showing positive outcomes in two long COVID patients treated with sequential bilateral SGB. His research coordinator, Deborah Duricka, PhD, has been the driving force behind the subsequent studies.
The clinical data:
It's important to be candid: the evidence base is promising but still early-stage, consisting entirely of uncontrolled studies—case reports, retrospective chart reviews, and small pilot studies. There are no published randomized controlled trials with sham/placebo arms yet.
Here's what exists:
Liu & Duricka case series (2021): Two long COVID patients treated with SGB, both reporting sustained symptom improvement—implicating dysautonomia in long COVID pathophysiology.
Retrospective cohort, Colorado (2023): A 41-patient cohort study from a chronic pain management practice found that 86% of patients experienced a reduction in their long COVID symptoms following SGB. Patients had been symptomatic for 3 to 29 months.
Duricka & Liu retrospective chart review (2024): Following their initial case report, they analyzed patients treated with the same bilateral SGB protocol over six months in their clinic, finding significant self-reported reductions in fatigue, cognitive problems, sleep disturbance, anxiety, and depression.
Pilot study (2024): A 17-patient study found that 94% showed moderate-to-severe autonomic dysfunction before treatment, all reported some symptomatic improvement, and there were statistically significant reductions in fatigue severity scores (p = 0.002) and heart rate (p = 0.008).
Prospective cohort pilot, ME/CFS (2025): The most recent study, funded by the Solve ME/CFS Initiative, used weekly sequential bilateral SGBs for three weeks in patients meeting criteria for both long COVID and ME/CFS, measuring cognition, orthostatic intolerance, cortisol levels, and sleep. Results showed that SGB significantly reduced sympathetic symptoms, and notably, measures of cognitive impairment improved, particularly in immediate and delayed recognition.
