FACT SHEETS
Stellate Ganglion Blocks (SGB)
Stellate ganglion blocks are diagnostic and/or therapeutic procedures for pain conditions related to sympathetic nervous system dysfunction. The procedure consists of injecting local anesthetic (and sometimes other medications) around the stellate ganglion, a collection of sympathetic nerve cell bodies located in the neck.
If the patient experiences significant pain relief or changes in sympathetic function while the medication is active, this suggests that sympathetic nervous system activity is contributing to their pain or symptoms. This confirms the diagnosis and provides therapeutic benefit simultaneously.
This injection procedure targets the stellate ganglion which controls sympathetic nerve activity to the head, neck, upper extremities, and upper chest, potentially interrupting pain signals and improving blood flow to these areas. The approach typically involves careful needle placement near the C6 or C7 vertebra under imaging guidance.
Stellate ganglion blocks have proven effective for multiple conditions beyond traditional pain management, including:
Complex regional pain syndromes affecting the head, neck, arm, and upper quadrant, especially when associated with sympathetically maintained pain
Autonomic nervous system dysfunction, including hyperhidrosis (excessive sweating), Raynaud's phenomenon, and certain vascular disorders
Post-traumatic stress disorder (PTSD) and other trauma-related conditions that impact the autonomic nervous system, where the procedure may help reset sympathetic tone and reduce hyperarousal symptoms
Should a stellate ganglion block provide significant but temporary relief, repeated injections may be recommended as part of a comprehensive treatment plan. For some patients, this may be followed by other interventions such as physical therapy, medication adjustments, or consideration of more permanent sympathetic blockade if conservative treatments fail to provide adequate long-term relief.
THE DIAGNOSIS FOR USE OF STELLATE GANGLION BLOCKS (SGB)
Pain and dysfunction related to the sympathetic nervous system commonly manifests as burning pain, sensitivity to touch, temperature changes, swelling, or color changes in the face, neck, and upper extremities. Sympathetic nervous system dysregulation can result from trauma, surgery, viral infections, or may develop without clear cause, and these conditions are often diagnosed clinically rather than through specific imaging findings.
To target sympathetic nerve activity, we inject local anesthetic (and sometimes other medications) around the stellate ganglion, a cluster of sympathetic nerve cell bodies located at the base of the neck. We access this structure using precise image guidance—typically fluoroscopy or ultrasound—to ensure accurate placement and safety.
Research indicates that stellate ganglion blocks can provide significant relief for patients with sympathetically maintained pain, including complex regional pain syndrome (CRPS), certain facial pain conditions, and vascular disorders of the upper extremities. More recently, evidence suggests benefits for post-traumatic stress disorder and other conditions involving autonomic nervous system dysfunction.
For patients with sympathetically mediated conditions, stellate ganglion blocks can be used as part of a comprehensive treatment plan that may include physical therapy, medication management for concurrent psychiatric symptoms, and in some cases, consideration of more permanent sympathetic modulation if conservative treatments fail to provide adequate long-term relief.
INJECTION PROTOCOL
The primary purpose of the injection is to block sympathetic nervous system activity and potentially alleviate pain and related symptoms. Consequently, implementing a consistent measurement method for both pain and sympathetic symptoms is essential. The Visual Analog Scale (VAS) is commonly used for pain assessment, rating pain from 0 to 10—where 0 represents no pain and 10 indicates extreme pain that completely inhibits thinking, movement, and normal functioning.
Patients should continue their regular medication schedule prior to the procedure, except for blood thinners which may need to be temporarily discontinued (only after consultation with your physician). For the procedure to be appropriately evaluated, patients should keep track of their symptoms before and after the injection, including not only pain levels but also changes in skin temperature, color, and sweating patterns in the affected areas.
THE PROCEDURE
The injection requires inserting a needle through the skin under fluoroscopic (X-ray) or ultrasound guidance. The needle is carefully guided to the anterior surface of the C6 or C7 vertebra where the stellate ganglion is located. Contrast dye may be used to confirm proper placement and rule out vascular uptake before the medication is injected.
It's perfectly normal to feel anxious about the procedure. However, you can be reassured that these injections are performed routinely, generally involve minimal discomfort due to local anesthetic use, and usually take less than 30 minutes to complete. Following the injection, you may experience temporary effects that indicate a successful block, including a drooping eyelid (Horner's syndrome), redness of the eye, nasal congestion, and warmth in the affected arm. These effects are expected due to the temporary interruption of sympathetic nerve signals and typically resolve as the local anesthetic wears off, usually within several hours.