What Are Gallstones

Abdominal Pain
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The gallbladder is a pear-shaped organ that sits under your liver. It acts as a storehouse for bile, which is a fluid produced by your liver to help your body digest fat. When you eat food that contains fat, your gallbladder releases bile through a tube called the common bile duct. It then is released into your small intestine to help your body break down and absorb the fat.

You are most likely to have problems with your gallbladder if something blocks the flow of bile through the bile ducts.

The cause of this is usually a gallstone. The type of gallbladder disease that results from gallstones is called Cholelithiasis.


What Causes Gallstones?

The bile stored in the gallbladder contains water, bile salts, cholesterol, fats, proteins, and bilirubin. Bile salts break up the fat that is consumed in the food we eat. The bilirubin gives the bile and ours stools their yellowish color.

Gallstones can form in the gallbladder when bile hardens into stone-like material. Bile can harden if there is too much bile salts, cholesterol, or bilirubin in it.


Types of Gallstones

There are two types of gallstones -- cholesterol stones and pigment stones. Cholesterol stones are the most common type of gallstone to develop, occurring in approximately 80% of patients with gallstones.

Cholesterol stones are made mostly of hardened cholesterol, and are usually yellowish-green in color.

Pigment stones are made of bilirubin, and are the stones are usually small and dark in color.

Gallstones can be as small as grains of sand or as big as golf balls. Smaller stones are more common, though bigger stones do develop. When I had my gallbladder removed, the surgeon found six large stones, each approximately one inch in diameter.


What Problems Can Occur If You Have Gallstones

Many people who have gallstones don't have symptoms.

Others may think their symptoms are because of a different disorder.

The most common problem caused by gallstones occurs when a gallstone blocks the cystic duct of the gallbladder, which takes bile to and from the gallbladder. The pain that can occur with this blockage is what is often referred to as a gallbladder attack. The pain, which is usually severe, can last a few minutes to several hours.

Gallstones can block other ducts. These include the hepatic ducts, which carry bile from the liver, and the common bile duct, which takes bile from the cystic and hepatic ducts to the small intestine.

When bile becomes trapped in one of the ducts, inflammation can occur in the gallbladder or the ducts. In rare cases, if bile is trapped in the hepatic duct, inflammation of the liver can occur. A gallstone can also block the pancreatic duct, a duct which carries digestive enzymes from the pancreas. When the pancreatic duct is blocked, the digestive enzymes are trapped, and a painful inflammation can occur. This condition is called gallstone pancreatitis.

Complications can occur when there are gallstones. If gallstones block the ducts for an extended period of time, severe, possibly fatal, damage or infections can occur in the gallbladder, the liver, or the pancreas.

If you experience a fever, jaundice, or persistent pain, seek immediate medical attention.


For further information on gallstones:



"Common Gastrointestinal Problems - Gallstones." American College of Gastroenterology. 9 Sep 2008.

"Gallstones." American College of Gastroenterology. 9 Sep 2008.

"Gallstones." NIH Publication No. 07–2897 July 2007. National Digestive Diseases Information Clearinghouse (NDDIC). 9 Sep 2008.