What is sphincter of Oddi dysfunction?

The sphincter of Oddi is a muscular valve in your digestive tract. It helps move bile and juices from your pancreas into your small intestine. When this valve doesn’t work right, it’s called sphincter of Oddi dysfunction (SOD).

Bile is a digestive juice that your liver makes. Your gallbladder stores it. Then it flows into the upper part of your small intestine to help you digest food. At the same time, your pancreas makes juices that are important for digestion. Both bile and your pancreatic juices flow to your small intestine through a common duct that is opened and closed by the sphincter of Oddi.

In one type of SOD, the sphincter of Oddi goes into spasm. It clamps shut and can’t relax. Other times it may be narrowed from past inflammation. Your digestive juices back up into your pancreas and into the bile ducts of your liver. This causes intense belly pain.

Another type of SOD happens when the sphincter of Oddi becomes stiff and narrow. This prevents digestive juices from entering your small intestine.

What causes sphincter of Oddi dysfunction?

Experts aren’t sure why SOD happens. It is a rare condition.

Who is at risk for sphincter of Oddi dysfunction?

You’re most at risk for this condition if you’ve had your gallbladder removed. Other risk factors for SOD are: 

• Having had gastric bypass weight-loss surgery

• Being female

• Being middle-aged

• Having pancreatitis that keeps coming back (recurrent pancreatitis)

What are the symptoms of sphincter of Oddi dysfunction?

The main symptom of SOD is severe stomach pain that comes and goes. The symptoms can feel similar to a gallbladder attack. You may have pain in your upper belly that seems to move, or spread, into your right shoulder. You may also have chest pain that feels like a heart attack. This pain is often very similar to gallbladder pain. But people still have this pain after their gallbladder is removed.

Sometimes SOD causes pancreatitis. Pancreatitis is a severe swelling and irritation of the pancreas. It may cause stomach pain around the belly button and pain in the left side under the ribs. Symptoms that go along with the belly pain include:

• Nausea

• Vomiting

• Loss of appetite

• Weight loss

How is sphincter of Oddi dysfunction diagnosed? 

Your healthcare provider may think you have SOD if you have recurrent pancreatitis or bouts of stomach pain after your gallbladder was taken out. Your provider may also consider SOD if you have severe belly pain after recovering from a gastric bypass surgery. 

Treatment for SOD does not help stomach pain that is not caused by SOD. So it is very important to do testing to find out if you truly have the condition. These tests may include: 

• Blood tests. These are done to check for higher-than-normal liver or pancreatic enzymes.

• Ultrasound. This imaging test may be done to look at the bile duct, liver, or pancreas.

• Magnetic resonance cholangiopancreatography. This is an imaging study of the bile and pancreatic ducts.

• Endoscopic retrograde cholangiopancreatography (ERCP). This test looks directly inside the duct system while getting X-ray images, taking visual pictures, and measuring pressure.

• Endoscopic ultrasound. This internal ultrasound is done during an upper GI (gastrointestinal) exam. It uses a thin tube (endoscope) that is put into the mouth, down into the stomach, and into the first part of the small intestine. This test gives very detailed images. It is able to look for causes of pain, such as chronic pancreatitis.

• Hepatobiliary iminodiacetic acid scan. This is a special type of scan that looks at the drainage out of the biliary system

How is sphincter of Oddi dysfunction treated? 

Treatment of SOD depends on the type you have. It also depends on how bad your symptoms are. Your healthcare provider may advise:

• Certain medicines. Calcium channel blockers and other medicines may ease symptoms. But they can have side effects.

• Sphincterotomy. For this procedure, your sphincter of Oddi muscle is cut surgically. You may have this done if tests show that your symptoms are due to a backup of digestive juices into your liver or pancreas. And you are having symptoms often. This can be done through surgery, or more often endoscopy.

• Botulinum toxin (Botox) injection. Botox injection may be done through an endoscope to ease symptoms.

What are possible complications of sphincter of Oddi dysfunction?

The main complication of SOD is pancreatitis. This can be severe. It can occur from the ERCP procedure or treatment done during the procedure. If you have surgery to cut the sphincter, other possible complications are:

• Bleeding

• Infection

• Delayed narrowing of the duct system because of scarring

How do I manage sphincter of Oddi dysfunction?

If you have SOD or if you are recovering from sphincterotomy, follow all your healthcare provider’s orders. Take all your medicines as directed. Tell your healthcare provider about any other medicines you take, including over-the-counter medicines, supplements, or herbs.

These tips may help you manage SOD:

• Don’t drink alcohol.

• Don’t smoke.

• Limit high-fat foods.

• Keep your cholesterol under control.

• Stay at a healthy weight.

• Eat smaller meals more often.

When should I call my healthcare provider?

Call your healthcare provider if you have severe stomach pain that is not going away or keeps coming back. Also tell your healthcare provider if you have these symptoms, especially after gallbladder surgery:

• Fever

• Chills

• Nausea

• Vomiting

• Loss of appetite

Key points about sphincter of Oddi dysfunction

• The sphincter of Oddi is a muscular valve in your digestive tract. When it doesn’t work right, it’s called sphincter of Oddi dysfunction (SOD).

• The sphincter of Oddi helps move bile and juices from your pancreas into your small intestine.

• You are more at risk for SOD if you have your gallbladder removed or have gastric bypass weight-loss surgery.

• The main symptom of SOD is severe stomach pain that comes and goes.

• Blood tests, ultrasound, and other imaging tests can help diagnose this condition.

• A sphincterotomy may help ease the symptoms of SOD.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.

• Before your visit, write down questions you want answered.

• Bring someone with you to help you ask questions and remember what your provider tells you.

• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.

• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.

• Ask if your condition can be treated in other ways.

• Know why a test or procedure is recommended and what the results could mean.

• Know what to expect if you do not take the medicine or have the test or procedure.

• If you have a follow-up appointment, write down the date, time, and purpose for that visit.

• Know how you can contact your healthcare provider if you have questions.