Research & Evidence

Effectiveness of Combined Cognitive Processing Therapy with Stellate Ganglion Block: An Open-Label Randomized Wait-List Clinical Trial

Psychotherapy and Psychosomatics

↳ N=86 military personnel and veterans. SGB before CPT produced faster PTSD symptom reduction. Non-responders to CPT achieved significant PCL-5 improvement after receiving SGB — establishing SGB as a powerful augmentation to first-line therapy.

• •86 military personnel and veterans randomized to SGB-before-CPT vs. SGB-after-CPT
• •Both groups showed significant PCL-5 reduction from baseline (p < 0.001)
• •SGB-before-CPT group achieved faster symptom relief
• •CPT non-responders at week 8 showed significant PCL-5 improvement after receiving SGB at week 12
• •Supports SGB as an augmentation to evidence-based psychotherapy, not a replacement

Fig. 2a — Mean PCL-5 scores over 52 weeks. Blue: SGB-before-CPT group. Red: SGB-after-CPT group. Blue dashed line = SGB timing; gray shading = massed CPT; red dashed line = crossover SGB for control group. Both groups converge by week 13, but SGB-before-CPT achieves faster initial reduction.

Reversible Increased Anxiety Following Left-Sided Stellate Ganglion Block to Treat Posttraumatic Stress Disorder: A Case Report

Military Medicine

↳ Rare safety finding: in two patients, left-sided SGB temporarily worsened anxiety after prior right-sided benefit. Subsequent right-sided SGB fully resolved worsening and improved symptoms beyond original baseline.

• •Two patients experienced acute anxiety worsening after left-sided SGB following successful right-sided SGB
• •Worsening was fully reversible in both cases
• •Subsequent right-sided SGB resolved symptoms and improved beyond pre-treatment baseline
• •Estimated incidence: rare — mechanism unknown
• •Clinical implication: if left-sided SGB worsens symptoms, repeat right-sided SGB is the rescue intervention

Long-Term Durability of Bilateral Two-Level Stellate Ganglion Blocks in Posttraumatic Stress Disorder: A Six-Month Retrospective Analysis

Clinical and Translational Neuroscience

↳ 75 patients — 96% (72/75) showed PCL-5 improvement at 6 months, with an average 55.48% reduction from baseline. The first study to establish 6-month durable PTSD symptom relief following bilateral two-level SGB.

• •75 patients analyzed at 1 week, 1 month, 3 months, and 6 months post-bilateral SGB
• •96% (72/75) showed PCL-5 improvement at 6-month follow-up
• •Average 55.48% reduction in PCL-5 scores from baseline to 6 months
• •Results stratified by trauma type: public service/childhood abuse patients responded earliest; sexual abuse trauma patients showed greatest gains at 6 months
• •First published study establishing 6-month durability for bilateral two-level SGB in PTSD

PCL-5 scores at baseline, 1 week, 1 month, 3 months, and 6 months post-bilateral 2-level SGB (n=75). Male, female, and total scores all show sustained improvement through 6 months, with scores remaining well below the clinical PTSD threshold.

Three-Month Durability of Bilateral Two-Level Stellate Ganglion Blocks in Patients with Generalized Anxiety Disorder: A Retrospective Analysis

Brain Sciences

↳ 86.8% of 114 GAD patients improved. Average GAD-7 dropped 52% (15.5 → 7.3) and held at 3 months across all initial severity levels.

• •114 patients (71 male, 43 female) with generalized anxiety disorder
• •99 of 114 patients (86.8%) achieved lasting improvement
• •Baseline GAD-7: 15.52 → 3-month follow-up: 7.28 (52% average improvement)
• •Benefit sustained regardless of initial anxiety severity
• •First study to establish 3-month durability for GAD specifically

Decrease in 105 patients' GAD-7 scores following bilateral two-level stellate ganglion block (2LSCB). All severity subgroups showed meaningful reduction from baseline to 3-month follow-up.

Three-Month Durability of Bilateral Two-Level Stellate Ganglion Blocks for Traumatic Brain Injury: A Retrospective Analysis

Biomedicines

↳ 85.4% of 41 TBI patients improved, with an average 48.4% decrease in NSI scores sustained at 3 months. No significant difference in outcomes between male and female patients.

• •41 patients (28 male, 13 female) with chronic mild TBI
• •35 of 41 patients (85.4%) showed NSI score improvement
• •Average 48.4% decrease in total NSI scores from baseline
• •Effects durable at 3-month follow-up
• •No significant sex differences in treatment response

Total NSI scores at baseline, 1 week, 1 month, and 3 months post-SGB (n=19 with complete follow-up). All three groups — male, female, and total — show sustained improvement.

The Effect of Bilateral, Two-Level Cervical Sympathetic Chain Blocks on Specific Symptom Clusters for Traumatic Brain Injury, Independent of Concomitant PTSD Symptoms

Brain Sciences

↳ All 20 patients showed ~50% improvement in pure TBI symptoms (isolated from PTSD overlap) at 1 week and 1 month — confirming SGB benefits TBI independently of any PTSD effect.

• •20 patients analyzed using a novel NSI sub-score excluding PTSD/anxiety-overlapping items
• •TBI-specific sub-score: baseline 15.45 → week 1: 8.30 → month 1: 7.80 (~50% improvement)
• •All 20 patients demonstrated improvement
• •First study isolating TBI-specific SGB benefit independent of PTSD symptom improvement
• •Supports SGB for TBI patients regardless of PTSD comorbidity

Three-Month Durability of Bilateral Two-Level Stellate Ganglion Blocks in Patients with Generalized Anxiety Disorder: A Retrospective Analysis

Brain Sciences

↳ 86.8% of 114 GAD patients improved. Average GAD-7 dropped 52% (15.5 → 7.3) and held at 3 months across all initial severity levels.

• •114 patients (71 male, 43 female) with generalized anxiety disorder
• •99 of 114 patients (86.8%) achieved lasting improvement
• •Baseline GAD-7: 15.52 → 3-month follow-up: 7.28 (52% average improvement)
• •Benefit sustained regardless of initial anxiety severity
• •First study to establish 3-month durability for GAD specifically

Decrease in 105 patients' GAD-7 scores following bilateral two-level stellate ganglion block (2LSCB). All severity subgroups showed meaningful reduction from baseline to 3-month follow-up.

Stellate Ganglion Block Reduces Anxiety Symptoms by Half: A Case Series of 285 Patients

Journal of Personalized Medicine

↳ 50% reduction in anxiety scores across 285 patients — exceeding twice the clinically important threshold. Bilateral blocks outperformed unilateral.

Stellate Ganglion Block in the Treatment of Long COVID: A Systematic Review

Current Pain and Headache Reports

↳ Systematic review of 7 studies. Symptom improvement rates ranged from 55.8% to 100%. Most robust improvements (>80%) seen in cough, dyspnea, headache, joint pain, and paresthesias. Confirms SGB as a promising intervention warranting controlled trials.

• •Searched EMBase and PubMed through August 2025 — 45 results, 7 studies met inclusion criteria
• •Symptom improvement rates across all 7 studies: 55.8% to 100%
• •Most robust improvements (>80%): cough, dyspnea, headache, joint pain, pain intensity, paresthesias
• •Highly responsive symptom categories: autonomic dysfunction (76.7%), brain fog (71.6%), fatigue (69.8%), sleep disruption (72.2%), dizziness (70%), anxiety (68.8%), mood/depression (69.2%)
• •Authors characterize SGB as 'promising' and call for standardized controlled trials with larger cohorts

Stellate Ganglion Block for the Management of Long COVID Symptoms: A Retrospective Cohort Study

Cureus

↳ Multi-center study (Harvard/Brigham & Women's, UVA, Allegheny) — 52 patients, average 3 SGB injections. 55.8% reported short-term improvement. Most responsive: brain fog, fatigue, dizziness, headache.

• •52 patients across 3 Boston-area pain centers (Sept 2022–Sept 2024); mean symptom duration 2.6 years
• •Average 3 SGB injections per patient; ultrasound-guided cervical sympathetic chain block
• •55.8% reported at least short-term symptom improvement
• •Most responsive symptoms: brain fog, fatigue, dizziness, headache (median 3–4.5 point improvement on severity scale)
• •Post-exertional malaise showed minimal improvement
• •Authors conclude SGB 'reduced the severity of many PASC symptoms' and call for randomized controlled trials

Stellate Ganglion Block Relieves Long COVID-19 Symptoms in 86% of Patients: A Retrospective Cohort Study

Published September 2023

↳ 86% of 41 long COVID patients (symptoms 3–29 months) experienced symptom relief after unilateral or bilateral SGB. Brain fog (79%), fatigue (77%), and joint/muscle pain (94%) showed among the highest relief rates.

• •41-patient cohort study — 18 male / 23 female, age 18–89, symptoms lasting 3–29 months
• •Unilateral or bilateral SGB used depending on symptom severity
• •Mechanism: SGB resets marked sympathetic hyperactivity observed during and after COVID-19 infection
• Symptom Relief Rates
• •Brain fog: 79% (80% of patients affected)
• •Fatigue: 77% (85% of patients affected)
• •Post-exertional malaise: 74% (66% of patients affected)
• •Joint and muscle pain: 94% (39% of patients affected)
• •Shortness of breath: 88% (41% of patients affected)
• •Dizziness: 77% (41% of patients affected)
• •Mood changes: 76% (39% of patients affected)
• •Tachycardia or palpitations: 78% (22% of patients affected)
• •Pins and needles sensation: 100% (22% of patients affected)
• •Sleep issues: 71% (34% of patients affected)
• •Diarrhea: 88% (20% of patients affected)
• •Cough: 80% (24% of patients affected)
• •Chest pain: 80% (24% of patients affected)
• •Change in taste or smell: 40% (44% of patients affected)
• •Rash: 100% (5% of patients affected)