Navigating a diagnosis of Functional Biliary Disorder (FBD) or Sphincter of Oddi Dysfunction (SOD) can feel incredibly isolating. This page is designed to help you understand these complex conditions, guide you through the diagnostic process, and connect you with a supportive community. We want you to know you are not alone in this journey.
What is Functional Biliary Disorder?
The biliary system is part of the digestive system. It includes the liver, gallbladder and bile ducts, which work together to produce, store and transport bile.
Bile plays an important role in digestion, particularly in helping the body digest fats.
A functional disorder means that there is a problem with how part of the system is working, rather than necessarily an obvious structural abnormality such as gallstones or another blockage.
Functional biliary disorders are recognised within the Rome IV classification of disorders of gut-brain interaction. Rome IV includes functional gallbladder disorder and functional biliary Sphincter of Oddi disorder within its category of gallbladder and Sphincter of Oddi disorders.
For patients, however, the terminology can be particularly confusing because different healthcare professionals may use different terms, and the terminology used to describe SOD has evolved over the years.
What is the Sphincter of Oddi?
The Sphincter of Oddi is a small muscular valve located where the bile duct and pancreatic duct empty into the small intestine.
Its job is to help control the flow of:
– Bile from the liver and gallbladder
– Pancreatic juices from the pancreas
The sphincter normally opens and closes to regulate the movement of these digestive fluids into the intestine.
When the sphincter does not function normally, it may affect the flow of bile and/or pancreatic secretions.
This is where the term Sphincter of Oddi Dysfunction (SOD) comes in.
What is Sphincter of Oddi Dysfunction?
Sphincter of Oddi Dysfunction (SOD) is a term that has historically been used to describe problems involving the function of the Sphincter of Oddi.
People with suspected SOD may experience episodes of significant upper abdominal pain, sometimes alongside nausea, vomiting or other digestive symptoms.
SOD has traditionally been divided into different types, but medical terminology has changed as our understanding of these conditions has developed.
The older Type I, Type II and Type III SOD classification is no longer used in the same way within the Rome IV system. In particular, the previous Type III category has been discarded because evidence showed that sphincterotomy did not provide better outcomes than a sham procedure for this group.
Today, doctors may instead use terms such as functional biliary Sphincter of Oddi disorder, depending on the patient’s symptoms and investigation results.
This can make researching your condition confusing — particularly if you have been given a diagnosis of SOD in the past.
What Does Biliary Pain Feel Like?
One of the key features considered when assessing functional biliary disorders is biliary-type pain.
According to the Rome IV criteria, biliary pain is typically:
- Located in the upper central abdomen (epigastrium) and/or the upper right side of the abdomen.
- Builds to a steady level.
- Lasts for 30 minutes or longer.
- Occurs at different intervals rather than being present every day.
- Is severe enough to interrupt normal activities or result in an emergency department visit.
- Is not significantly related to bowel movements.
- Is not significantly relieved by changing position or taking acid-suppressing medication.
Nausea and vomiting can occur alongside biliary pain, and the pain may sometimes radiate towards the back or right shoulder blade.
It is important to remember that not everyone experiences these conditions in exactly the same way.
Other Symptoms People May Experience
Depending on the individual and the underlying problem, people with suspected functional biliary disorders may experience symptoms such as:
Abdominal Pain
Pain can be severe and may occur in the upper abdomen, particularly around the right upper quadrant or epigastric area.
Nausea and Vomiting
Episodes of pain may be accompanied by significant nausea or vomiting.
Digestive Problems
Some people experience bloating, indigestion, early fullness or difficulties eating.
Pain after Gallbladder Removal
Sphincter-related disorders are often considered in people experiencing biliary-type pain following cholecystectomy (gallbladder removal), although there are many possible causes of pain after gallbladder surgery.
Pancreatitis
Some patients with disorders involving the pancreatic side of the Sphincter of Oddi experience recurrent episodes of pancreatitis. However, pancreatitis has many possible causes, so other causes need to be investigated and excluded.
Diagnosis and Understanding
One of the most frustrating aspects of these conditions is that there may not be a single test that provides an immediate answer.
Symptoms can overlap with many other gastrointestinal and abdominal conditions.
Doctors may therefore need to consider and exclude other possible causes before reaching a diagnosis.
Investigations may include blood tests and imaging, depending on the symptoms and individual circumstances.
For suspected functional biliary Sphincter of Oddi disorder, the Rome IV criteria include biliary pain alongside either elevated liver enzymes or a dilated bile duct, but not both, and the absence of bile duct stones or another structural abnormality. Other tests, including sphincter manometry and hepatobiliary scintigraphy, may sometimes provide supporting information, although their role and usefulness can be debated.
This is one reason diagnosis can become a long and complicated process.
The relationship between the gallbladder and the Sphincter of Oddi can make these conditions particularly difficult to understand.
Some people develop symptoms before having their gallbladder removed, while others experience ongoing or new biliary-type symptoms following gallbladder surgery.
Removing the gallbladder does not necessarily resolve symptoms if the underlying problem involves another part of the biliary system.
At the same time, persistent pain after gallbladder removal does not automatically mean that someone has SOD. There are many potential causes of post-cholecystectomy pain, which is why careful assessment is important.
The word functional can sometimes be misunderstood.
It does not mean that symptoms are imaginary, psychological or “all in your head”.
In modern gastroenterology, functional gastrointestinal disorders are understood as disorders of how the digestive system functions. Rome IV describes these conditions within the broader category of disorders of gut-brain interaction.
Patients’ symptoms can be very real and can substantially affect their physical health, emotional wellbeing, relationships, work, and everyday life.
Treatment Options
Day-To-Day Management
Medication
Helps manage pain and other symptoms, tailored to the individual.
Diet & Lifestyle
Adjustments that some patients find helpful alongside other treatment.
Related Digestive Issues
Treatment for bloating, indigestion or other symptoms alongside FBD.
Specialist-Led Care
Gastroenterology Care
Ongoing input from a specialist experienced in functional biliary disorders.
Botox Injections
Used by some specialists to temporarily relax the Sphincter of Oddi.
Other Specialist Treatment
Additional options based on individual symptoms and investigations.
Procedures - Specialist Assessment Required
Endoscopic Procedures
Considered only for selected patients, after careful specialist assessment.
ERCP & Sphincterotomy
More invasive options that carry risks, including pancreatitis.
Terminology Glossary
SOD / Sphincter of Oddi Dysfunction
The term historically used to describe problems with the function of the Sphincter of Oddi. Still widely used, though current classification is more specific.
Biliary pain
A specific pattern of pain described within the Rome IV criteria — see ‘What does biliary pain feel like’ above. This term underpins most of the diagnoses below.
Functional biliary Sphincter of Oddi disorder
The term used within the Rome IV classification for a specific group of patients with biliary pain and certain objective findings.
Functional gallbladder disorder
A separate functional biliary condition involving biliary pain in the absence of gallstones or another structural problem.
Pancreatic Sphincter of Oddi disorder
A separate category involving recurrent pancreatitis after other causes have been excluded, alongside specific diagnostic findings.
If you have been diagnosed with Functional Biliary Disorder or Sphincter of Oddi Dysfunction, or you are still searching for answers, you are not alone.
Our Foundation provides information, support, and a community for people affected by these conditions.
You can explore our resources, read other patients’ experiences, and learn more about the different aspects of Functional Biliary Disorder.
Read Patient Stories
Discover the real experiences of people living with FBD and SOD.
Find Support
Explore the support and resources available through the Foundation.
Learn More
Understand more about the investigations and terminology you may encounter.
Get Involved
Help us raise awareness and improve understanding of Functional Biliary Disorder.