Sympathetic Nerve Block

Medically reviewed by Drugs.com. Last updated on Apr 6, 2025.

• Care notes
• Ambulatory
• Discharge
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AMBULATORY CARE:

What you need to know about a sympathetic nerve block:

A sympathetic nerve block is an injection of anesthesia medicine around nerves near your spine. You may need a sympathetic nerve block to locate an area of pain or to relieve nerve pain. It may also be used to control heavy sweating or relieve Raynaud syndrome. Your healthcare provider may recommend a series of nerve blocks if your pain or condition improves after the first.

How to prepare for a sympathetic nerve block:

• Your healthcare provider will tell you how to prepare. You may be told not to eat or drink anything for a certain time before your procedure. You may need to arrange to have someone drive you home after the procedure.
• Tell your provider if you or anyone in your family has ever had problems with anesthesia.
• Tell your provider about all the medicines you take, including vitamins and herbs. Your provider will tell you if you need to stop any medicine for the nerve block, and when to stop. Your provider will tell you which medicines to take or not take on the day of your nerve block.

What will happen during a sympathetic nerve block:

• Your healthcare provider will ask you to rate your symptoms before the procedure. You will stay awake and alert during the procedure so you can answer questions.
• Your provider will find the area of the nerve group to be treated. Fluoroscopy (an x-ray that produces moving images), CT scans, or an ultrasound may be used to find the area. Anesthesia will be injected into the nerve group area.
• Your provider will again ask you to rate your symptoms.

What to expect after a sympathetic nerve block:

• Healthcare providers will monitor you until you are fully alert. You may be able to go home when providers see you are okay.
• You may not be able to feel pain in the nerve block area for several hours. You will need to be careful so you do not injure the area.

Risks of a sympathetic nerve block:

You may have numbness, weakness, or trouble walking. Your blood pressure may get too high or too low. You may have anxiety, dizziness, or seizures if the anesthesia gets into your blood vessels. You may have bleeding, or a blood clot may form if the needle goes into a blood vessel. The needle may also go into other parts of your body and cause damage. If the needle goes into a nerve, you may feel burning, tingling, prickling, or severe pain.

Drugs used to treat this and similar conditions

Call your local emergency number (911 in the US) if:

• You have a seizure.
• You have trouble breathing.

Seek care immediately if:

• You develop hives or swelling.
• You have severe pain.

Call your doctor or neurologist if:

• You are dizzy or have ringing in your ears.
• You feel numbness or tingling around your mouth.
• You have numbness or weakness in a limb 8 hours or more after your procedure.
• You continue to bleed at the site of the needle insertion.
• You have questions or concerns about sympathetic nerve blocks.

Self-care:

Your healthcare provider may give you specific instructions. The following are general safety guidelines:

• Rest the day after the nerve block. Your provider will tell you when you can drive and return to work or your normal daily activities.
• Keep pressure off the area. Prop the area or surround it with pillows while you sleep. This will keep you from rolling over onto the area. Change positions often to keep you from putting direct pressure on the area.
• Protect the area from injury. Move slowly and carefully so you do not bump the numbed body part. Do not touch anything that might be hot. You might not feel the skin burn until it is severe. Protect the area in hot and cold weather.
• Keep a record of your symptoms and activities. Include the date if your symptoms return.

Follow up with your doctor or neurologist as directed:

Bring your symptom record to your follow-up visits. Write down your questions so you remember to ask them during your visits.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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