A celiac plexus block is an injection that delivers pain-relieving medication directly to a bundle of nerves in the abdomen, interrupting pain signals from the upper belly organs. It’s most commonly used for people with severe abdominal pain from pancreatic cancer or chronic pancreatitis, though it can treat pain originating from several other organs as well.
The Celiac Plexus and What It Does
The celiac plexus is a dense network of nerve fibers located deep in the abdomen, sitting just below the diaphragm and in front of the aorta, roughly behind the stomach and pancreas. It sits at about the level of the lowest thoracic and first lumbar vertebrae. The plexus contains clusters of nerve cell bodies (ganglia) that vary from person to person, typically numbering one to five and ranging from half a centimeter to over four centimeters in size.
This nerve network acts as a relay station for pain signals from most of the upper abdominal organs: the stomach, liver, gallbladder, bile ducts, pancreas, and upper portion of the small intestine. It does not carry pain signals from the left colon, rectum, or pelvic organs. When any of these upper abdominal organs are diseased or inflamed, the celiac plexus is the highway those pain signals travel along to reach the brain. A celiac plexus block works by interrupting that highway.
Block vs. Neurolysis: Two Different Goals
There are two distinct versions of this procedure, and the difference matters. A celiac plexus block uses a long-acting local anesthetic, sometimes combined with a steroid to reduce inflammation around the nerves. This provides temporary relief lasting weeks to months. It’s often used as a diagnostic step to confirm that the celiac plexus is actually the source of the pain, or for conditions where the pain may improve over time on its own.
Celiac plexus neurolysis goes further. Instead of numbing the nerves temporarily, it uses a chemical agent (most often alcohol, less commonly phenol) to destroy the nerve fibers. Alcohol is preferred because it carries a lower risk of permanent nerve damage, though it does cause more pain during the injection itself. Neurolysis typically provides relief for two to six months and is used more often in cancer-related pain, particularly from pancreatic tumors, where long-lasting relief is the priority.
Who Benefits Most
Pancreatic cancer is the most common reason for this procedure. The pancreas sits directly in front of the celiac plexus, so tumors there frequently press on or invade these nerves, causing deep, relentless abdominal pain that can be difficult to control with medication alone. A celiac plexus block or neurolysis can reduce or eliminate the need for opioid painkillers in these patients, which also means fewer opioid side effects like constipation, nausea, and sedation.
Chronic pancreatitis is another frequent indication. Beyond those two conditions, the procedure is sometimes used for pain from liver cancer, gallbladder disease, and other upper abdominal cancers. A single-center review of 72 blocks performed for non-cancer abdominal pain found that 67% were effective overall. Among temporary blocks specifically, 72% provided meaningful relief for an average of about 37 days. Permanent (neurolytic) blocks had a 50% effectiveness rate but lasted longer when they worked, with a median duration of 90 days.
How the Procedure Works
The procedure is performed while you lie face down (for a back approach) or on your side. You’ll receive sedation to keep you comfortable but typically remain awake enough to communicate. The entire process usually takes 30 to 60 minutes.
There are two main approaches. The percutaneous method involves inserting a needle through the skin of the back, guided by CT scan or fluoroscopy (real-time X-ray) to ensure precise placement near the celiac plexus. A contrast dye is injected first to confirm the needle is in the right spot before the medication is delivered. The endoscopic ultrasound approach uses a flexible scope passed through the mouth and into the stomach, with an ultrasound probe at the tip that provides a direct view of the celiac plexus through the stomach wall. The needle is then passed through the stomach wall to reach the nerves. This approach offers more direct access and allows for precise placement.
Regardless of approach, the basic steps are the same: position the needle, confirm placement with imaging, inject the anesthetic (and steroid or neurolytic agent as planned), then monitor you in recovery.
What to Expect Afterward
You’ll spend time in a recovery area after the procedure, where staff will monitor your blood pressure and watch for any immediate reactions. Most people go home the same day but need someone to drive them because of the sedation. Soreness at the injection site is normal and typically resolves within a few days.
Pain relief doesn’t always kick in immediately. Some people notice improvement within hours, while for others it takes a day or two, especially if a steroid was included (steroids take longer to reach their full effect). It’s common for the procedure to be repeated if the first block wears off or provides only partial relief.
Common and Serious Side Effects
The most frequent side effects are relatively mild. A temporary drop in blood pressure occurs in roughly 1 to 3% of patients and can last up to five days. This happens because the celiac plexus helps regulate blood vessel tone in the abdomen, so blocking it can cause blood to pool there, leading to lightheadedness when you stand up. Diarrhea is also common for the same reason: the nerves that slow gut movement are temporarily silenced, so the intestines become more active. Both of these effects usually resolve on their own.
Other common side effects include bruising, swelling, or soreness at the injection site, muscle spasms, and infection at the treatment site.
Serious complications are rare but worth knowing about. They include allergic reactions to the anesthetic or contrast dye, bleeding behind the abdominal organs (retroperitoneal hematoma), injury to the kidneys or aorta, a collapsed lung (pneumothorax) when the back approach is used, and in extremely rare cases, lower extremity weakness or paralysis from damage to nearby spinal nerves. The endoscopic approach avoids some of the risks associated with passing a needle through the back, which is one reason it has become increasingly popular.
Who Should Not Have This Procedure
People with active infections near the injection site, significant bleeding disorders, or who are on blood thinners that cannot be safely paused are generally not candidates. Anatomical issues can also be a barrier: if a large tumor has distorted the normal anatomy around the celiac plexus so severely that safe needle placement isn’t possible, the procedure may be too risky. Allergies to local anesthetics or contrast dye need to be discussed beforehand, though alternatives or premedication can sometimes be arranged.