What Is a Celiac Plexus Block and How Does It Work?

A celiac plexus block is an injection-based procedure that interrupts pain signals traveling through the celiac plexus, a dense network of nerves nestled behind the stomach near the aorta. It is used primarily to treat severe upper abdominal pain from conditions like pancreatic cancer and chronic pancreatitis, and it works by numbing or destroying the nerve fibers that relay visceral pain from those organs to the brain. Roughly two-thirds of patients who receive the block experience meaningful pain relief, though the duration and degree vary widely depending on the underlying disease and the specific technique used.

What the Celiac Plexus Actually Does

Pain from the upper abdominal organs, including the pancreas, liver, gallbladder, stomach, and parts of the intestine, does not travel directly to the spinal cord the way pain from your skin or muscles does. Instead, those signals route through the celiac plexus, a cluster of nerve bundles located in the retroperitoneum at the root of the celiac trunk, the major artery that supplies blood to the upper abdomen.¹ Think of it as a relay station: visceral pain messages from these organs converge at this plexus before being forwarded up to the brain. By targeting this relay station with an injection, clinicians can cut off or dampen those signals at a single anatomical chokepoint.

This distinction matters for who the procedure can help. A celiac plexus block is effective against visceral pain, the deep, diffuse, hard-to-pinpoint ache that comes from organ involvement. It does not address somatic pain (from the abdominal wall or muscles) or neuropathic pain (from direct nerve damage by a tumor). Distinguishing between these pain types before the procedure is critical for clinical success.² If your pain is primarily visceral, the block stands a good chance of helping. If a tumor has invaded the abdominal wall or wrapped around spinal nerves, the block alone will not be enough.

Block Versus Neurolysis

You will hear two terms used almost interchangeably, but they describe meaningfully different procedures. A celiac plexus block uses a local anesthetic, sometimes combined with a steroid, to temporarily numb the nerve fibers. The effect typically lasts weeks to a few months and is reversible. A celiac plexus neurolysis uses a chemical agent, most commonly alcohol (ethanol) or phenol, to destroy the nerve fibers permanently. Neurolysis is generally reserved for patients with cancer-related pain who need longer-lasting relief and are not expected to need those nerve pathways again.

In a pilot study comparing phenol and ethanol for neurolysis, both agents reduced pain scores substantially within two hours, and there was no significant difference in pain relief rates at one week (about 83% with phenol and 69% with ethanol) or in how long the relief lasted. However, burning pain and inebriation occurred only in patients who received ethanol, not phenol.³ For patients who are alcohol-intolerant or have concerns about the burning sensation, phenol can be a useful alternative.

Who Gets a Celiac Plexus Block

The procedure is most closely associated with pancreatic cancer, where abdominal pain is extremely common and often difficult to control with medications alone. A Cochrane systematic review of trials in adults with pancreatic cancer found that celiac plexus block produced a modest but statistically significant reduction in pain scores compared to standard analgesic therapy at four weeks and at eight weeks. More striking was the impact on opioid consumption, which was significantly lower in the block group.⁴ In a study of 50 patients with pancreatic cancer, about three-quarters experienced effective pain relief during the first three months or until death after receiving the neurolytic version of the procedure.⁵

Chronic pancreatitis is the second major indication, though the evidence is less consistent. A recent systematic review and meta-analysis pooling over 600 patients found that about 64% achieved significant pain relief from the block, with slightly better rates in randomized trials (about 72%) than in observational studies.⁶ A multicenter cohort study tempered that optimism somewhat, finding that while the block reduced hospital visits, opioid use actually climbed over longer follow-up, suggesting the pain relief may be short-lived in chronic pancreatitis patients.⁷ The distinction makes intuitive sense: in cancer, the goal is palliation during a limited timeframe, while in chronic pancreatitis, the ongoing inflammatory process can re-establish pain pathways over months and years.

Beyond these two conditions, celiac plexus neurolysis has shown benefits for other upper abdominal cancers as well, reducing symptom burden related to pain, sleep, and quality of life in patients with nonpancreatic cancers that involve the upper abdomen.⁸ The block has also been used diagnostically in patients with median arcuate ligament syndrome, a condition where a band of tissue compresses the celiac artery. In one series, about 82% of patients with suspected median arcuate ligament syndrome reported symptom improvement after the block, helping surgeons decide who would benefit from an operation.⁹

How the Procedure Is Performed

There are several ways to reach the celiac plexus, and the choice of approach depends on the clinical situation, the available equipment, and the physician’s expertise. The three main categories are posterior percutaneous (through the back), anterior percutaneous (through the abdomen, less common), and endoscopic ultrasound-guided (through the mouth and stomach).

The posterior percutaneous approach is the classic technique. A needle is advanced through the back, usually under CT or fluoroscopic guidance, toward the area in front of the spine at the level of the first lumbar vertebra. Within this broad approach, there are important variations. The retrocrural technique places the needle behind the diaphragm, so the injected agent initially pools behind the aorta and tends to block the splanchnic nerves above the plexus rather than the celiac ganglia directly. The transaortic technique pushes the needle through the aorta itself so the tip sits right at the celiac artery’s origin, delivering the agent more precisely around the ganglia.¹⁰ The fact that the retrocrural approach often blocks the splanchnic nerves rather than the celiac plexus itself is sometimes seen as a feature rather than a bug, since the pain signals pass through those nerves on the way to the plexus anyway.

Endoscopic ultrasound-guided (EUS) celiac plexus block is increasingly popular. The endoscope is passed through the mouth into the stomach, where ultrasound imaging allows the physician to visualize the celiac region and inject directly through the stomach wall. A small randomized comparison found that half of EUS-guided block patients achieved significant pain relief with lasting benefit in some patients out to 24 weeks, compared to only a quarter for CT-guided block. The EUS approach was also less expensive and preferred by patients who experienced both.¹¹ That said, this was a small trial, and both approaches remain in wide clinical use.

Opioid-Sparing Effects

For many patients and their doctors, the most compelling reason to pursue a celiac plexus block is not just pain scores on a scale but the practical ability to reduce opioid use and its side effects. A retrospective case series of 13 palliative care patients with upper abdominal cancer found that median daily opioid consumption dropped from about 87 mg oral morphine equivalents at baseline to roughly 58 mg at four weeks, a reduction of more than 40% per patient. Opioid-related side effects dropped in parallel: nausea and vomiting fell from affecting more than half the patients at baseline to about a quarter at four weeks, and somnolence resolved entirely.¹² Other studies have similarly observed that the block reduces opioid needs and gastrointestinal side effects for at least four weeks, which can be a meaningful window for someone whose daily comfort is otherwise dominated by nausea, constipation, and drowsiness from pain medications.¹³

Does Timing Matter

A growing body of evidence suggests that performing the block earlier in the disease course, rather than waiting until pain becomes severe, leads to better outcomes. A retrospective cohort study comparing early versus delayed CT-guided celiac plexus neurolysis in advanced pancreatic cancer found that earlier intervention reduced pain escalation, lowered opioid use, and improved quality of life related to pain interference, though it did not extend survival.¹⁴ Since up to 80% of pancreatic cancer patients experience pain during their illness, there is an argument for discussing the procedure proactively rather than reserving it as a last resort. Research comparing nerve block before patients reach the higher rungs of the pain-medication ladder to intervention only after strong opioids have already been started found that earlier treatment led to better response rates and lower opioid consumption over the following year.¹⁵

The practical takeaway: if you or a loved one has been diagnosed with pancreatic cancer and is starting to experience abdominal pain, it is worth raising the topic of a celiac plexus block with the oncology or palliative care team early, rather than waiting until pain medications are no longer sufficient.

Safety and Side Effects

The most common side effects are transient and expected consequences of disrupting the autonomic nerves in the region. Diarrhea and temporary worsening of abdominal pain are frequently reported, and a drop in blood pressure (orthostatic hypotension) is common because the celiac plexus also carries sympathetic nerve fibers that help maintain vascular tone. In the meta-analysis of EUS-guided blocks for chronic pancreatitis, the most frequent complications were diarrhea and transient pain exacerbation, with no reported deaths.¹⁶

Serious complications are rare but worth knowing about. Persistent orthostatic hypotension has been described in case reports, including one patient who required corticosteroid treatment for prolonged low blood pressure after a neurolytic block.¹⁷ The most feared complication is lower extremity weakness or paralysis, which can occur if the neurolytic agent damages or causes spasm in the artery of Adamkiewicz, a blood vessel that supplies the spinal cord. This can lead to spinal cord ischemia and, in the worst cases, permanent paraplegia.¹⁸ A case report described a patient who developed temporary lower extremity weakness likely due to vasospasm of the anterior spinal artery, possibly triggered by the needle, the alcohol, or the epinephrine used during the procedure.¹⁹ These catastrophic events are exceedingly rare, but they underscore why the procedure should be performed by experienced practitioners with proper image guidance.

Bilateral or Unilateral Injection

When the block is done from the back, the physician can place needles on both sides of the spine (bilateral) or on just one side (unilateral). A systematic review and meta-analysis comparing the two approaches in patients with pancreatic cancer found no significant difference in short-term pain relief or overall response rates. However, only the bilateral approach was associated with a statistically significant reduction in postoperative analgesic use.²⁰ A separate prospective cohort study found the bilateral approach offered slightly better early pain relief, but over longer follow-up the outcomes and safety profiles converged.²¹ In practice, the bilateral technique is often preferred when feasible, but a unilateral approach is a reasonable alternative when anatomy or patient positioning makes double-needle placement difficult.

Splanchnic Nerve Block as an Alternative

Because the splanchnic nerves feed into the celiac plexus from above, blocking them achieves a similar functional result. A comparative study found that splanchnic nerve block and celiac plexus block produced clinically comparable pain relief over six months in patients with upper gastrointestinal tumors.²² In patients with chronic nonmalignant abdominal pain, however, a retrospective analysis found that splanchnic nerve block at the T11 vertebral level lasted significantly longer than celiac plexus block, with a median duration of 56 days versus 21 days, and produced a greater reduction in pain severity.²³ This suggests the splanchnic nerve block may be the better choice when the pain is nonmalignant and the goal is to avoid repeating the procedure too frequently. For cancer pain, where neurolysis is typically the end goal anyway, the difference matters less.

Radiofrequency Ablation of the Celiac Ganglia

A newer approach uses radiofrequency energy, delivered through a needle under endoscopic ultrasound guidance, to thermally destroy the celiac ganglia rather than chemically dissolving them with alcohol or phenol. A randomized controlled trial comparing EUS-guided radiofrequency ablation to conventional EUS-guided neurolysis in pancreatic cancer patients found that the radiofrequency group reported less pain and better quality of life across multiple measures, with fewer gastrointestinal symptoms and better emotional functioning.²⁴ Early case reports using a dedicated radiofrequency device showed pain dropping substantially within days, with some patients able to stop opioids entirely.²⁵ This approach is still relatively new and not yet widely available, but it may eventually offer more precise nerve destruction with fewer of the chemical side effects associated with alcohol injection.

Quality of Life and What the Block Cannot Do

A large randomized controlled trial examined whether neurolytic celiac plexus block improved quality of life or survival compared to standard analgesic therapy in patients with unresectable pancreatic cancer. The findings were sobering on both fronts: quality of life declined gradually over time in both groups, with no significant difference between those who received the block and those who did not. Survival was also similar between groups.²⁶ This is an important reality check. The block can reduce pain and lower opioid needs, but it does not halt the progression of the underlying disease, and the gradual physical decline that comes with advanced cancer tends to erode quality-of-life scores regardless of how well pain is managed.

That said, the picture is more encouraging when you look at specific dimensions of quality of life rather than overall scores. Research on both pancreatic and nonpancreatic abdominal cancers has found that celiac plexus neurolysis can improve sleep quality and reduce the broader symptom burden beyond pain alone.²⁷ For a patient who is sleeping poorly because of constant abdominal aching, a successful block can make a real difference in daily functioning even if the overall trajectory of the illness remains unchanged.

Use in Children and Adolescents

Celiac plexus block is overwhelmingly studied and used in adults, but a small body of work suggests it may have a role in younger patients too. A pilot study of 13 pediatric patients who underwent EUS-guided celiac plexus block, some for chronic pancreatitis and others for severe functional dyspepsia, found that those with pancreatitis experienced more sustained relief, averaging about 12 weeks, while the functional dyspepsia group improved for closer to 5 weeks.²⁸ In the oncology setting, a case series of children and young adults with cancer found that pain scores improved after the block in all patients, and opioid needs dropped in the first week, though disease progression eventually overrode the benefit in those with limited survival.²⁹ The data are thin enough that no firm guidelines exist for pediatric use, but the early signals are encouraging enough that some centers offer it as part of a multimodal pain plan for selected younger patients.

Cost Considerations

Pain management in advanced cancer is expensive, driven largely by medications, repeated hospitalizations, and emergency visits. A study evaluating the health economics of percutaneous celiac plexus ablation found that medication-specific costs and total healthcare costs were significantly lower in patients who received the procedure compared to those managed with drugs alone, even though the hospitalization and examination costs were similar between groups.³⁰ The savings largely came from reduced opioid and adjuvant medication use. For patients and families already dealing with the financial strain of cancer treatment, this is a practical consideration worth discussing with the care team alongside the clinical benefits.