Gallstones are hardened deposits that form inside your gallbladder, and what they “do” depends entirely on where they are and whether they’re moving. Most gallstones sit quietly and never cause problems. But when a stone shifts and blocks one of the narrow ducts that carry bile, it can trigger intense pain, inflammation, or serious complications in the pancreas and liver. Roughly 5 to 25% of adults in the United States have gallstones, and many never find out unless an imaging scan picks them up by accident.
How Gallstones Form
Your gallbladder stores bile, a digestive fluid made by the liver that helps break down fats. Bile contains cholesterol, bile salts, and a fat called phosphatidylcholine. Under normal conditions, bile salts and phospholipids keep cholesterol dissolved. Gallstones form when that balance tips: either too much cholesterol enters the bile, or there aren’t enough bile salts to keep it in solution. The excess cholesterol separates out as tiny crystals, which clump together over weeks or months into stones. About 80% of gallstones are this cholesterol type.
A sluggish gallbladder accelerates the process. If the gallbladder doesn’t empty well after meals, bile sits longer than it should, giving crystals more time to grow and merge into visible stones. Stones can be as small as a grain of sand or as large as a golf ball, and some people develop a single stone while others have dozens.
The remaining gallstones are pigment stones, made primarily from calcium and bilirubin (a waste product from broken-down red blood cells). Brown pigment stones typically form in the bile ducts rather than the gallbladder itself and are linked to chronic bacterial infections that alter bile chemistry.
What Happens When a Stone Stays Put
The majority of gallstones do nothing. They float in bile inside the gallbladder without blocking anything or irritating the walls. A large meta-analysis found that among people with asymptomatic gallstones, only about 2 out of 100 develop symptoms in any given year. After five years, roughly 10% will have experienced pain. After 15 years, that number rises to about 26%. The rest continue on without ever knowing the stones are there.
Because of these low odds, the standard approach for silent gallstones is simply to leave them alone. Surgery isn’t recommended unless symptoms appear.
Biliary Colic: The Classic Gallstone Attack
When a gallstone gets pushed into the cystic duct (the exit tube from the gallbladder), the resulting pain is called biliary colic. Most people feel it under the right ribcage, though it often radiates to the right shoulder or back. The pain is steady and intense, not crampy, and an episode lasts anywhere from 20 minutes to several hours.
Fatty meals are the most common trigger. When fat reaches your small intestine, it signals the gallbladder to squeeze and release bile. That contraction can force a stone into the duct opening. If the stone passes through on its own, the pain resolves. If it lodges, the pain persists until the stone either slips back into the gallbladder or moves forward into the common bile duct.
Nausea and vomiting often accompany the pain. Attacks tend to recur, and once you’ve had one episode, the likelihood of another increases. Eating smaller, lower-fat meals can reduce the frequency of attacks by limiting how forcefully the gallbladder contracts.
What Happens When a Stone Blocks the Common Bile Duct
The common bile duct carries bile from the gallbladder and liver into the small intestine. When a gallstone lodges here, bile can’t drain. It backs up into the liver and eventually leaks into the bloodstream. The visible result is jaundice: a yellow tint to the skin and whites of the eyes, along with darker urine. Stools may turn pale or clay-colored because bile pigments aren’t reaching the intestine.
A blocked common bile duct also creates a breeding ground for bacteria. The stagnant bile can become infected, a condition called cholangitis, which causes fever, chills, and worsening pain. This is a medical emergency that requires urgent drainage of the duct.
Gallstone Pancreatitis
The common bile duct and the pancreatic duct share a single opening where they empty into the small intestine. If a gallstone blocks that shared opening, bile can reflux into the pancreatic duct. This triggers premature activation of digestive enzymes inside the pancreas, essentially causing the organ to start digesting itself. The result is acute pancreatitis: severe upper abdominal pain that bores through to the back, often with vomiting and a rapid heart rate.
Gallstones are one of the two most common causes of acute pancreatitis. The condition ranges from mild (resolving in a few days with fasting and IV fluids) to life-threatening if the pancreas becomes severely inflamed or infected.
Chronic Gallbladder Inflammation
Repeated episodes of gallstones blocking and unblocking the cystic duct cause ongoing irritation to the gallbladder wall. Over time, the gallbladder can become chronically inflamed, thickened, and scarred. It gradually loses its ability to store and release bile efficiently. Symptoms of chronic cholecystitis tend to be subtler than acute attacks: recurring bloating, indigestion after meals, and a dull ache under the right ribs.
If a stone completely obstructs the cystic duct and stays there, acute cholecystitis develops. The trapped bile irritates and inflames the gallbladder wall, causing persistent pain (lasting longer than a few hours), fever, and tenderness. Without treatment, the gallbladder can develop gangrene or rupture.
Who Is Most Likely to Develop Gallstones
Several factors raise your risk. Being overweight or obese increases the amount of cholesterol secreted into bile, particularly in women. Rapid weight loss is another major trigger. When you lose weight quickly, your liver releases extra cholesterol into bile, and the gallbladder may not empty as effectively. Very low-calorie diets and weight-loss surgery both carry elevated gallstone risk for this reason.
Other well-established risk factors include age over 40, female sex (estrogen increases cholesterol in bile), a family history of gallstones, and certain genetic variations that affect cholesterol transport. Pregnancy, with its hormonal shifts and gallbladder sluggishness, also raises risk.
Treatment and Gallbladder Removal
Laparoscopic cholecystectomy, the surgical removal of the gallbladder through small incisions, remains the standard treatment for symptomatic gallstones. It’s one of the most commonly performed surgeries, and most people go home the same day or the next. Recovery typically takes one to two weeks for desk jobs, a bit longer for physical work.
A non-surgical option exists: a bile acid medication that gradually dissolves small cholesterol stones over 6 to 12 months. But the recurrence rate is over 50%, which is why surgery is almost always preferred when symptoms are present.
Life Without a Gallbladder
Your body doesn’t need a gallbladder to digest food. Without it, bile flows directly from the liver into the small intestine in a slow, continuous drip instead of being stored and released in concentrated bursts. Most people adjust without difficulty.
However, somewhere between 5 and 47% of people who have their gallbladder removed experience some ongoing digestive changes. The most common complaints are bloating, vague abdominal discomfort, and indigestion. Some people develop loose stools or diarrhea because excess bile acids reach the colon, where they pull in water. These symptoms often improve over the first few months as the body adapts, though for a small percentage of people they persist long-term. Eating smaller meals and reducing fat intake can help manage them.