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.

The sphincter of Oddi has three major functions: 1) regulation of bile and pancreatic flow into the duodenum, 2) diversion of hepatic bile into the gallbladder, and 3) the prevention of reflux of duodenal contents into the pancreaticobiliary tract.

Four distinct smooth muscle sphincters are present in the GI tract: the lower esophageal sphincter (LES), the pyloric sphincter (PS), the ileocecal sphincter (ICS), and the internal anal sphincter (IAS). This chapter examines how tone generation contributes to the functional behavior of these sphincters.

The sphincter of Oddi refers to the smooth muscle that surrounds the end portion of the common bile duct and pancreatic duct. This muscle relaxes during a meal to allow bile and pancreatic juice to flow into the intestine.

The sphincter regulates the secretion of pancreatic juice and bile into the duodenum. It also prevents reflux of duodenal contents into the ampulla of Vater. The sphincter of Oddi is relaxed by the hormone cholecystokinin via vasoactive intestinal peptide.

The symptoms of sphincter of Oddi dysfunction may come and go over time. They also may vary in severity from one occurrence to the next. Common symptoms include: abdominal pain, which is the most prevalent symptom (usually epigastric or right upper quadrant pain)

People with SOD may benefit from trying some of the following general dietary tips:

• avoiding alcohol.
• eating a low-fat diet.
• maintaining a normal cholesterol level.
• eating smaller, more frequent meals.
• avoiding spicy foods.
• eating foods high in fiber.
• maintaining a healthy weight.

Sphincters are specialized muscles that are located at the upper esophagus (upper esophageal sphincter (UES)), gastroesophageal junction (lower esophageal sphincter (LES)), antroduodenal junction (pylorus), ileocecal junction (ICJ), and the anus (anal sphincter).

Foods to avoid

• coffee and other caffeinated beverages.
• chocolate.
• red meat and pork, even when cut lean.
• fried, fatty, or greasy foods.
• spicy foods.
• alcohol.
• fruits, especially acidic fruits.
• fibrous raw vegetables.

For people with mild symptoms, a doctor may recommend medication as the first-line of treatment. Medications usually consist of nitrate and calcium channel blockers, which can help to reduce spasms and alleviate symptoms. People with more severe SOD may require surgery.

The mechanism of sphincter of Oddi dysfunction is not completely known but, in theory, when an individual has SOD, his/her sphincter goes into “spasm”, causing temporary back-up of biliary and pancreatic juices, resulting in attacks of abdominal pain.

Sphincter of Oddi (SO) is located where the common bile duct and the pancreatic duct connect to the duodenum. The SO opens after we have eaten so as to allow bile from the gallbladder, and enzymes from the pancreas, to enter the duodenum so as to break down food components for absorption into the body.

There is effectively an obstruction at the level of the sphincter, which may be due to fibrosis, inflammation, or elevated sphincter tone. This prevents bile and pancreatic juice from flowing properly to the small intestine, leading to a backup of digestive juices that can cause severe pain in the abdomen.

ERCP is rarely indicated if gallbladder is not removed. When sphincter of Oddi manometry has confirmed that the pressures are high, sphincterotomy gives good relief in more than half of patients.