Gallstones are stones or lumps that develop in the gallbladder or bile duct when certain substances harden.

The gallbladder is a small sac located on the right-hand side of the body, on the underside of the liver. Some of the chemicals that exist in the gallbladder can solidify into either one large stone or several small ones.

There are approximately 20 million Americans with gallstones. A 2008 study revealed that the prevalence of gallstones in adults in industrialized countries was around 10 percent and appeared to be rising.

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The majority of people with gallstones experience no symptoms at all. This is because the stones stay in the gallbladder and cause no problems.

Sometimes, however, gallstones may lead to cholecystitis, or an inflamed gallbladder.

The primary symptom is pain that comes on suddenly and quickly gets worse. This pain can occur on the right side of the body, just below the ribs, between the shoulder blades, or in the right shoulder.

Other symptoms include:

  • nausea
  • vomiting
  • sweating
  • restlessness

Doctors only treat gallstones if they have caused gallbladder inflammation, blockage of the bile ducts, or if they have moved from the bile ducts into the intestines.

Treatments for gallstones include:

Cholecystectomy

Cholecystectomy means the surgical removal of the gallbladder. This is usually performed with laparoscopic surgery. Laparoscopic surgery is not possible for about 10 percent of people, who will need open cholecystectomy.

With open cholecystectomy, a large cut is made in the abdomen. People who undergo open surgery require a longer hospital stay and recovery time. If a person’s gallbladder is severely inflamed, they generally will need open surgery.

For a large proportion of those who undergo a cholecystectomy, gallstones come back within a year. To help prevent this, doctors give many people with gallstones ursosdeoxycholic acid, which is the acid found in bile.

Ursodeoxycholic acid

Ursosdeoxycholic acid lowers the cholesterol content of bile, making it less likely that stones will form.

If a gallstone is made of cholesterol, it can sometimes be slowly dissolved with ursodeoxycholic acid. This type of treatment, known as dissolution, may take up to 24 months to be effective. It is not as effective as surgery but is sometimes the only choice for people who cannot have a general anesthetic.

Endoscopic retrograde cholangiopancreatolography

When a person with gallstones cannot have surgery or ursodeoxycholic acid, they may undergo endoscopic retrograde cholangiopancreatolography (ERCP), which requires a local anesthetic.

A doctor places a flexible fiber-optic camera, or endoscope, into the person’s mouth, then passes it through the digestive system and into the gallbladder.

An electrically heated wire widens the opening of the bile duct. The doctor can then remove the stones or leave them to pass into the intestine.

Lithotripsy

A doctor aims ultrasonic shock waves at the gallstones to break them up. If gallstones become small enough, they can then pass safely in a person’s stools. This type of treatment is uncommon and is only used when there are few gallstones present.

In many cases, a medical professional will discover a person’s gallstones by accident when treating the person for a different condition. A doctor may suspect gallstones after a cholesterol test, an ultrasound scan, a blood test, or even an X-ray.

The doctor may use blood tests to look for signs of infection, obstruction, pancreatitis, or jaundice.

Other diagnostic tests include:

Cholangiography

A medical professional injects a dye either into the bloodstream, so that it concentrates into the bile ducts or gallbladder, or straight into the bile ducts using an ERCP. The dye shows up on X-rays.

The doctor will then be able to look at the X-rays and identify possible gallbladder or bile duct disorders, such as pancreatitis, cancer of the pancreas, or gallstones. The X-rays will indicate to the doctor whether the dye is reaching the liver, bile ducts, intestines, and gallbladder.

If the dye does not move into one of these areas, it generally means that a gallstone is causing a blockage. An expert will have a better idea of where the gallstone is located.

The medical professional can also use ERCP to locate and remove stones in the bile duct.

CT scan

This is a non-invasive X-ray that produces cross-section pictures of the inside of the human body.

Cholescintigraphy (HIDA scan)

A medical professional injects a small amount of harmless radioactive material into the patient. This is absorbed by the gallbladder, which the medical professional then stimulates to contract. This test may diagnose abnormal contractions of the gallbladder or an obstruction of the bile duct.

It used to be the case that doctors would advise people with gallstones who were not yet ready for surgery to follow an extremely low-fat diet to prevent gallstone growth.

Researchers have recently concluded this approach is less helpful than previously thought, as rapid weight loss can cause gallstones.

Instead, the recommendation is that people with gallstones eat a balanced diet with regular meals. This will not cure gallstones, but it can have a positive impact on any symptoms and pain.

Avoiding foods high in saturated fats such as butter, hard cheese, cakes, and cookies can help reduce the risk of gallstones developing. Cholesterol is thought to have a role in forming gallstones.

People can also make positive dietary steps changes to help prevent the condition, such as eating more nuts and consuming less alcohol.

Gallstones may form when the chemicals in the gallbladder are out of balance, such as cholesterol, calcium bilirubinate, and calcium carbonate.

There are two main types of gallstones.

Cholesterol gallstones may form if there is too much cholesterol in the bile. They are the main type of gallstones in the United States.

Pigment gallstones form when the bile has too much bilirubin. They are more common among people with liver disease, infected bile tubes, or blood disorders, such as sickle-cell anemia.

Experts are not completely sure why some people develop the chemical imbalance in their gallbladder that causes gallstones, while others do not.

However, gallstones are more common among people with obesity, especially women. A study revealed that having a waist size of 36 inches or more almost doubles a woman’s chances of developing gallstones and the need for surgery to remove them.

Other risk factors for gallstones include:

  • having been pregnant
  • having a family history of gallstones
  • having recently lost lots of weight
  • taking oral contraceptives
  • being sedentary
  • undergoing high-dose estrogen therapy
  • having a gene variant that significantly increases the risk of developing gallstones
  • having a high intake of dietary fat
  • being over 60 years of age
  • having Native American heritage
  • taking cholesterol-lowering drugs called statins
  • having diabetes

More women get gallstones than men. In addition, men who intentionally lost weight rapidly and then regained it may have an increased risk for gallstones later in life.

Additionally, research has linked hormone replacement therapy (HRT) for women during menopause to a higher risk of gallbladder problems. A study found that HRT administered by skin patches or gels poses a smaller risk than HRT taken orally.

Below is a 3-D model of gallstones, which is fully interactive.

Explore the model using your mouse pad or touchscreen to understand more about gallstones.

If the bile duct or duodenum are blocked by gallstones, it can block the flow of digestive juices to the pancreas. This can cause jaundice and acute pancreatitis. Treatment usually involves the surgical removal of the gallbladder.

It is common for people who have had their gallbladder removed to experience feelings of bloating and indigestion, especially when they have a high-fat meal. Some may pass stools more often than before.

Living without a gallbladder

A person can survive without a gallbladder. The liver produces enough bile to digest a normal diet. If a person’s gallbladder is removed, the bile reaches the small intestine from the liver via the hepatic ducts, rather than being stored in the gallbladder.

A small proportion of people who have had their gallbladder removed will experience softer and more frequent stools for a while because their bile flows into the small intestine more often.

Other complications

Other potential complications of gallstones include:

Biliary colic

When a stone gets stuck in the opening of the gallbladder and will not easily pass through, the contraction of the gallbladder may cause severe pain. When this happens, an individual may experience a painful condition called biliary colic.

The pain is felt in the upper part of the abdomen, but can also exist in the center or to the right of the abdomen. Pain is more common about an hour after eating, especially if an individual has had a high-fat meal.

The pain will be constant, last a few hours, and then subside. Some people will experience non-stop pain for 24 hours, while others may experience waves of pain.

Infection

If the gallstones have caused a gallbladder infection, the person with the condition may have a fever and experience shivering. In the majority of gallstone infection cases, people will be hospitalized for the removal of the gallstone.

Jaundice

If a gallstone leaves the gallbladder and gets stuck in the bile duct it may block the passage of bile into the intestine. The bile will then seep into the bloodstream, causing signs of jaundice.

In most cases, this complication will require the surgical removal of the gallstone. For some people, the gallstone eventually passes into the intestine.

Pancreatitis

If a small gallstone passes through the bile duct and blocks the pancreatic duct, or causes a reflux of liquids and bile into the duct, an individual may develop pancreatitis.

A person can’t change some of the factors that can increase their risk of developing gallstones, such as age, sex, and ethnic origin.

However, it is possible that following a vegetarian diet may reduce the risk of developing gallstones. Vegetarians have a significantly lower risk of developing gallstones compared with people who eat meat.

Many experts say that a diet low in fat and high in fruit and vegetables, including plenty of dietary fiber, also may help protect people from developing gallstones.

A person may also try controlling body weight to help prevent the formation of gallstones. However, crash dieting and rapid weight loss increase the risk of developing gallstones.

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