What Is a Stellate Ganglion Block?

A stellate ganglion block is a minimally invasive injection that targets a collection of sympathetic nerves called the stellate ganglion, located in the lower part of the neck. These nerves are part of the sympathetic nervous system, which regulates involuntary functions such as blood flow, temperature, sweating, and certain pain pathways.

In some conditions, the sympathetic nervous system becomes overactive and sustains or amplifies pain and other symptoms. A stellate ganglion block works by temporarily interrupting these signals, helping to reduce pain, inflammation, and abnormal nerve activity in the head, neck, upper extremity, and sometimes even stress-related conditions.

This procedure can be both diagnostic (confirming sympathetic involvement) and therapeutic (providing symptom relief).

What Conditions Can It Treat?

Stellate ganglion blocks are commonly used for:

• Complex Regional Pain Syndrome (CRPS) of the upper extremity

• Chronic neuropathic arm or hand pain

• Post-surgical nerve pain

• Post-traumatic nerve injury

• Herpes zoster (shingles) related pain

• Certain vascular conditions of the upper limb

• Refractory facial pain in select cases

• Some cases of PTSD and stress-related autonomic dysregulation (emerging use)

CRPS affecting the arm or hand is one of the most common indications. Symptoms may include:

• Burning pain

• Swelling

• Skin color or temperature changes

• Excessive sweating

• Extreme touch sensitivity

By calming the sympathetic chain, the procedure may reduce the abnormal feedback loop sustaining the pain.

How the Procedure Works

The stellate ganglion lies along the front of the cervical spine near the C6–C7 level.

Using ultrasound or fluoroscopic (x-ray) guidance, your physician carefully places a needle near the stellate ganglion while avoiding critical nearby structures such as blood vessels, the esophagus, and the airway.

Step-by-step:

1. You lie on your back with slight neck extension.

2. The skin is cleaned and numbed with local anesthetic.

3. Imaging guidance ensures precise needle placement.

4. Contrast (if using fluoroscopy) may confirm proper positioning.

5. Local anesthetic is injected around the stellate ganglion.

The procedure typically takes 15–20 minutes and is performed on an outpatient basis.

What Happens After the Injection?

A successful stellate ganglion block often produces temporary changes known as Horner’s syndrome, which confirms the sympathetic nerves were effectively blocked. These may include:

• Drooping eyelid (temporary)

• Small pupil on the injected side

• Redness of the eye

• Nasal congestion

• Warmth in the face or arm

These effects are expected and typically resolve within several hours.

Many patients experience:

• Warmth in the affected arm

• Decreased burning pain

• Reduced swelling

• Improved range of motion

How Long Does Relief Last?

Relief duration varies based on the underlying condition.

• Diagnostic blocks may provide hours to days of relief.

• Therapeutic benefit may last weeks or longer.

• In CRPS or chronic neuropathic conditions, a series of injections may be recommended to progressively calm the nervous system.

For PTSD and certain autonomic conditions, response varies and is still being studied.

Benefits of a Stellate Ganglion Block

• Minimally invasive

• Outpatient procedure

• Can reduce burning neuropathic pain

• May improve circulation

• Helps confirm sympathetic involvement

• May improve participation in physical therapy

• Emerging evidence for autonomic reset in select stress-related disorders

Risks and Potential Side Effects

Stellate ganglion blocks are generally safe when performed under imaging guidance, but potential risks include:

• Temporary hoarseness

• Temporary difficulty swallowing

• Bruising at injection site

• Low blood pressure

• Bleeding or infection (rare)

• Nerve injury (very rare)

• Pneumothorax (extremely rare but possible due to anatomical proximity)

Your physician will review medications, especially blood thinners, before the procedure.

Recovery & Aftercare

• Plan for light activity the remainder of the day

• Avoid driving until temporary eye or voice changes resolve

• Monitor symptom improvement over the following days

• Keep a symptom log if additional injections are planned

Most patients resume normal activities the next day.

Frequently Asked Questions

Is the eye drooping dangerous?
No. Temporary Horner’s syndrome is expected and confirms that the sympathetic nerves were successfully blocked. It resolves as the anesthetic wears off.

Is this the same as a nerve root injection?
No. A stellate ganglion block targets sympathetic nerves, not spinal nerve roots.

Why might I need more than one injection?
Some chronic pain conditions involve persistent sympathetic overactivity. Repeated blocks may help progressively reduce this amplification effect.

Reference

Available at Cleveland Clinic: “Stellate Ganglion Block”