What are gallstones?
Gallstones are stone-like objects that develop in the gallbladder or bile ducts (the pipe-like system within the liver). Gallstones can range dramatically in size, from tiny grains of sand to golf ball-sized objects. Interestingly, small stones can often cause the most trouble. These are stones that can leave the gallbladder and get stuck. Larger stones tend to remain quietly in the gallbladder. It is important to know that many people who have gallstones are never bothered by them and may not know the stones are even there. In these cases, no treatment is needed.
What are gallstones made of?
Gallstones are made up of hardened materials in your body. Typically, there are two types:
- Cholesterol: Made up of fatty substances in the blood, cholesterol is found throughout the body. These are the most common type of gallstones.
- Pigment Stones (mainly made of bilirubin): This substance is created when red blood cells break down in the liver. Too much bilirubin can actually leak into the bloodstream and cause the skin and eyes to turn yellow (jaundice).
Gallstones that are made up of cholesterol tend to be greenish in color. It is more common to have gallstones made of cholesterol than other types of stone.
Where do gallstones develop?
Gallstones are most commonly found in the gallbladder, as cholesterol stones. Gallstones can also travel from the gallbladder to the common bile duct, which is the largest of the ducts (pipes) in the liver.
Common bile duct stones are much less common than gallstones. Stones that find their way into the common bile duct can create more serious medical situations than just gallstones that remain in the gallbladder. Common bile duct stones can block the common bile duct, resulting in a serious infection called cholangitis. These stones can also cause pancreatitis, a painful condition caused by inflammation of the pancreas. Stones in the common bile duct can be removed without surgery by using a scope. Removal of the gallbladder requires surgery, which is typically done laparoscopically (a minimally invasive surgical procedure).
Illustration showing the gallstones and organs around the gallbladder.
What is the gallbladder?
The gallbladder is a small organ tucked up under the liver, on the right side of your body. It is shaped like a swollen pea pod. The gallbladder’s job is to store and dispense bile—a fluid that helps digest fats in the food you eat. Similarly to a pea pod, the gallbladder is green. This is due to the bile inside the gallbladder. Bile is a mixture of cholesterol, bilirubin, bile salts and lecithin.
The gallbladder is connected to other parts of the digestive system through a series of ducts, or tunnels. These ducts help to carry bile and aid in the entire process of breaking down food. Ultimately, the bile finds its way into the common bile duct, where it passes through a special sphincter (a valve made of muscle), into the small intestine. Once there, the bile can mix directly with food that’s waiting to be digested. The common bile duct then empties bile into the duodenum, the first portion of the very lengthy small intestine.
Not all bile travels directly from the liver into the duodenum. Another portion of bile moves from the liver into the gallbladder through a special duct called the cystic duct. The gallbladder stores bile, which is available to be used for digestion on very short notice. If a fatty meal is eaten, then the gallbladder is signaled to contract and to squeeze some stored bile into the common bile duct where it’s passed into the small intestine to mix with food. All bile ends up in the small intestine, where it helps digest food.
What is bile and what is it used for?
Produced in the liver, bile is a combination of cholesterol, bilirubin, bile salts and lecithin. This solution helps break down fat during the digestion process. Bile is either released directly to the small intestine from the hepatic duct (coming straight from the liver) or from the bile ducts after being stored in the gallbladder. The entire system of ducts is called the biliary system. Bile is an important part of digestion and exits the body with your feces.
Why do gallstones develop?
Gallstones can develop for several reasons, including:
- Forming when there is a critical concentration of cholesterol or bilirubin in the bile.
- Developing if the gallbladder is lazy and does not completely empty itself of bile.
- Occurring in people with other conditions, like:
- Cirrhosis of the liver.
- Blood disorders.
- During pregnancy.
- When you rapidly lose weight.
What are the symptoms of gallstones?
The symptoms of gallstones can vary based on the size of the gallstone. Most gallstones do not cause any symptoms at all. These gallstones are known as silent stones and require no treatment.
When the gallstones cause symptoms, they may include:
- Pain in the upper mid abdomen or upper right abdomen.
- Associated pain in the right shoulder.
- Chest pain.
- Nausea and vomiting.
- Repeated similar episodes.
- Jaundice (a yellow tint to the skin and eyes).
Pain is the main symptom most people experience with gallstones. This pain is steady and can last from around 15 minutes to several hours. The episodes, which can be severe, generally subside after one to three hours or so. People who have these painful attacks, while uncomfortable, are not in any medical jeopardy. Gallstones can cause acute cholecystitis, which is a more serious condition when the gallbladder is actually inflamed. This happens if a stone blocks off the cystic duct, which increases the pressure within the gallbladder. This condition may require antibiotics, hospitalization and even urgent surgery. Stones that pass out of the gallbladder and into the common bile duct can cause a complete blockage of the duct with jaundice, infection and pancreatitis.
You may feel pain in several places, including:
- Upper part of the abdomen, on the right side.
- Between the shoulder blades.
- Under the right shoulder.
When people experience pain with gallstones, it is sometimes referred to as a gallbladder attack or biliary colic.
There are two special conditions that could mimic gallstone symptoms. First, some gallbladders contain a thick sludge, which has not formed into actual stones. Sometimes sludge is felt to cause symptoms similar to actual gallstone pain. Secondly, there is an uncommon condition called acalculous cholecystitis, when the gallbladder becomes inflamed, but no stones are present. This is generally treated by surgical removal of the gallbladder.
Who is at risk for gallstones?
You may have an increased risk for developing gallstones if you:
- Are a woman.
- Are over the age of 40.
- Have a family history of gallstones (members of your family have had gallstones).
- Are overweight.
- Have lost a large amount of weight over a short amount of time.
- Have diabetes.
- Have Crohn’s disease.
- Eat a diet that is high in fat and cholesterol.
- Take drugs that lower cholesterol.
- Take various medicines including oral contraceptives.
- Have certain blood disorders.
- Are of Native American or Mexican descent.
Does my diet or weight place me at risk for gallstones?
People who are overweight or planning to lose weight –either through a planned diet program or a surgery—are actually at an increased risk of developing gallstones. The risk is higher for several reasons.
- People who are overweight may have diets that are high in cholesterol. Your bile has cholesterol in it already, but if your diet has excessive amounts of cholesterol, there is a higher chance it will collect in your bile and create a cholesterol gallstone.
- Rapid weight loss is also a concern. The gallbladder is a part of the digestive process. It holds bile to the side like a storage tank. Then the gallbladder releases the bile through the ducts and into the intestine to help break down food. If you go on a diet plan that significantly reduces your calorie intake or you have a weight loss surgery, your liver secretes extra cholesterol into the bile. The gallbladder can sometimes be ‘lazy’ and not able to contract vigorously, which also leads to gallstone formation. Patients who are undergoing a gastric bypass or other surgical procedure that will lead to rapid weight loss are at risk of gallstone formation. For this reason, surgeons may remove the gallbladder prophylactically (a preventive measure) at the time of the weight loss surgery.
If you are considering a weight loss program or surgery, it is important to discuss your risks with a doctor. This could be especially important if you have had stones in the past. It is common for gallstones to happen more than once.
Can children get gallstones?
Gallstones can happen to both children and adults. It is most common to see gallstones in middle-aged adults. However, adults are not the only ones who experience gallstones. One challenge with gallstones in children is identifying symptoms. Young children may have difficulty expressing where the pain is located. If you child has any unusual symptoms or abdominal pain, call your doctor.