The gallbladder is a pear-shaped pouch that sits just below the liver. It collects bile, a fluid made to help with digestion, as it flows from the liver to the intestine through the bile ducts. Gallstones are hardened bits of bile that form inside the gallbladder.
Bile makes it easier for you to digest fat. It also contains some waste products, including cholesterol and bilirubin, a substance created when old red blood cells are destroyed.
Gallstones form when cholesterol or bilirubin particles cluster together into a solid lump. The stone grows in size as the bile fluid washes over it, much like a pearl forms inside an oyster.
Most gallstones don't cause any symptoms or problems. Small ones can leave the gallbladder and its draining ducts, then pass out of the body through the intestines.
Gallstones can cause symptoms if they get caught in the narrow outlet of the gallbladder, or in the ducts that drain the gallbladder. After meals, especially meals high in fat, muscles in the wall of the gallbladder contract to help release bile into the intestines. It can be very painful if the gallbladder squeezes against a gallstone, or if a gallstone blocks bile from being released into the intestines.
More serious problems can develop if a gallstone gets into the drainage-duct system but doesn't make it all the way through to the intestines. In this case, the stone can cause a blockage, causing a buildup of bile in the gallbladder or liver. Since the digestive tract is teeming with bacteria, blocked fluid can lead to a very serious infection. If a gallstone lodges low down in the draining ducts, it can also block drainage of digestive enzymes from the pancreas. This can lead to inflammation of the pancreas (pancreatitis).
Gallstones are very common. About 1 in 5 women and 1 in 10 men have a gallstone by age 60. They are more likely to happen to older people, those who are overweight, and those who suddenly lose weight. Women who have had multiple pregnancies, taken birth control pills, or took estrogen after menopause are also more likely to develop gallstones.
Eighty percent of people with gallstones do not have any symptoms and do not need treatment. When gallstones do cause symptoms, they include:
- abdominal pain, usually high in the abdomen and often on the right side (where the gallbladder is located). The pain can spread to the back. Pain from gallstones can be steady or come and go. It can last between 15 minutes and several hours each time it occurs.
- sensitivity to high fat meals. Fats trigger the gallbladder to contract and can worsen pain.
- unexplained belching, gas, nausea, or a general decrease in appetite.
Gallstones can sometimes cause more serious problems such as pancreatitis or infections in the gallbladder or bile ducts. These can cause fever, more severe abdominal pain, or jaundice (a yellow color of the skin or whites of the eyes).
Most gallstones do not show up on regular X-rays, but they are seen easily with an ultrasound. Gallstones often don't cause symptoms. If you have symptoms that may or may not be due to gallstones, it may be difficult for your doctor to know if the stones are causing your symptoms even if you they show up on an ultrasound or CT scan.
If a stone is blocking the movement of bile, an ultrasound might show widened bile ducts. Your doctor may also order blood tests to evaluate injury to the liver and pancreas.
You are less likely to form gallstones if you avoid becoming overweight. If you are a dieter, try to avoid diets that cause you to lose weight very quickly, such as diets restricted to fewer than 500 calories daily.
Birth control pills and estrogen can increase the likelihood of gallstones. Consider avoiding these medications if you already have other risk factors for gallstones. Groups at high risk of gallstones include American Indians, Hispanics, people with sickle cell anemia and women who have had multiple pregnancies.
Gallstones require treatment only if they are causing symptoms. Smaller gallstones sometimes float out of the gallbladder on their own and are eliminated from the body in feces. Gallstone attacks can also calm down on their own if the bothersome stones shift position within the gallbladder. Even when gallstone symptoms go away on their own, they return within two years in about two of three people.
Most people whose gallstones cause symptoms will continue to have symptoms until the gallbladder is removed, although medications or procedures to break up the stones may also be used.
Surgical treatment for gallstones is highly effective. In most people, symptoms go away completely and stay away. The gallbladder is not a necessary organ and most people do not notice any digestive changes after it is removed. Sometimes abdominal pain or diarrhea develop after the gallbladder is removed, and additional treatment or changes in the diet are needed.
Removing the gallbladder is usually done with a minimally invasive ("keyhole) operation known as laparoscopic cholecystectomy. In this procedure, a surgeon makes one or more small openings in the abdomen. A camera, called a laparoscope, is placed into the abdomen through one of these openings. It lets the surgeon see what he or she is doing during the operation.
Using small instruments inserted into the abdomen through other small openings, the surgeon removes fluid and stones from the gallbladder to deflate it. The gallbladder can then be detached from the digestive system and removed through one of the openings.
People tend to recover very quickly from laparoscopic surgery because the surgical wounds are very small.
Open cholecystectomy can be a better option for gallbladder removal among people who have significant abdominal scarring from prior surgery or those who are very obese.
About 5% of the time, a surgeon starts a laparoscopic procedure but changes to an open cholecystectomy for technical reasons.
For stones caught in the common bile duct, an additional treatment called endoscopic retrograde cholangiopancreatography (ERCP) might be needed. A doctor uses miniature instruments attached to a camera at the end of a flexible tube called an endoscope. The endoscope is passed maneuvered from the mouth down the esophagus and into the intestine. The doctor can tug stones out of the bile duct, or can widen the lower part of the duct so they pass into the intestine on their own.
When surgery is not a good option, an oral medication known as ursodeoxycholic acid (Actigall) may help. It usually takes about six months to see results, and is effective only about half the time. Once the medication is stopped, gallstones are likely to return.
Two other ways to break up gallstones include:
- shockwaves (lithotripsy) to break apart the gallstones so they can pass out of the body on their own
- dissolving gallstones with chemicals injected directly into the gallbladder
Surgery is strongly preferred over these other treatments because stones are likely to form again if the gallbladder is not removed.