Gallstones are hardened deposits that form inside the gallbladder, the small organ under the liver that stores digestive fluid called bile. They can be as small as a grain of sand or as large as a golf ball, and they form when substances in bile, usually cholesterol, crystallize into solid pieces. Gallstones are common, affecting an estimated 10 to 15 percent of adults in the United States, but the vast majority never cause a problem and are found only by chance. When stones do cause symptoms, effective treatments are available, ranging from simply watching and waiting to a well-established outpatient surgery that resolves the problem for good. This guide explains what gallstones are, their symptoms, causes, how they are diagnosed, the treatments available, and the latest research.
What are gallstones?
Gallstones, known medically as cholelithiasis, are solid deposits that form inside the gallbladder when bile contains too much cholesterol or bilirubin, or when the gallbladder does not empty completely. Bile is a digestive fluid made by the liver and stored in the gallbladder, normally flowing into the small intestine to help digest fat. There are two main types: cholesterol stones, which are yellow-green and make up the large majority of cases in the United States, and pigment stones, which are darker and form from excess bilirubin. Some people develop a mix of both.
Gallstones are common, affecting an estimated 10 to 15 percent of adults in the United States, or roughly 25 million people, with about 1 million new cases diagnosed every year. The reassuring news is that most gallstones are silent, causing no symptoms and often turning up only by chance on a scan done for another reason, and silent stones generally need no treatment. Problems arise only when a stone blocks the flow of bile, which is why the distinction between a stone that is simply present and one that is actively causing trouble matters so much for how gallstones are managed.
Symptoms of gallstones
Most gallstones cause no symptoms and are discovered only incidentally, on a scan done for another reason. When a stone does cause symptoms, the hallmark is biliary colic: a sudden, intense pain in the upper right or center of the abdomen that builds quickly and can last from a few minutes to several hours. Biliary colic classically appears after a fatty or heavy meal, when the gallbladder contracts to release bile and a stone briefly blocks its exit, and the pain often spreads to the back or right shoulder blade with nausea or vomiting.
Gallstones occasionally lead to more serious problems when a stone stays lodged or a duct becomes blocked. Acute cholecystitis develops when a stone blocks the gallbladder’s outlet, causing inflammation with persistent pain, fever, and tenderness that, unlike ordinary biliary colic, does not ease on its own. A stone that migrates into the common bile duct can cause a blockage there, leading to jaundice, dark urine, and pale, clay-colored stools. One that blocks the shared opening of the bile and pancreatic ducts can trigger gallstone pancreatitis; gallstones are the leading cause of acute pancreatitis in the United States. Rarely, infected and obstructed bile ducts lead to acute cholangitis, a medical emergency marked by pain, fever, and jaundice together that can progress quickly to sepsis. Anyone with pain lasting several hours, a high fever or chills, yellowing skin or eyes, tea-colored urine, clay-colored stools, or persistent vomiting should seek care right away.
What causes gallstones and their risk factors
Gallstones form when the mix of substances in bile falls out of balance or the gallbladder does not empty as often as it should. Cholesterol stones develop when bile carries more cholesterol than it can keep dissolved, allowing crystals to form and slowly grow into stones. Bile cholesterol is not the same as the cholesterol measured on a routine blood test, but the two are connected closely enough that reviewing the total cholesterol blood test is a useful piece of a person’s broader metabolic picture. Pigment stones form differently, from an excess of bilirubin, a byproduct of the breakdown of red blood cells, and are more common with certain liver diseases, blood disorders, or infections.
A number of factors raise the risk of developing gallstones. Being a woman, especially during the childbearing years or while taking estrogen, roughly triples the risk, and risk also climbs after age 40. Obesity, a high-fat and low-fiber diet, diabetes, and a family history of gallstones all add to the risk, as does losing weight very quickly, including after weight-loss surgery. This is also why doctors have taken a closer look at popular GLP-1 weight-loss and diabetes medications, since rapid weight loss and slower gallbladder emptying may explain their link to higher gallstone risk. People of Native American or Mexican American descent face a higher risk, and certain medications can contribute too.
How gallstones are diagnosed
Abdominal ultrasound is the first and most important test for suspected gallstones, and it is highly sensitive at spotting stones in the gallbladder. It is quick, painless, uses no radiation, and is usually enough on its own to confirm the diagnosis. When results are unclear, or a complication such as a blocked duct or pancreatitis is suspected, doctors turn to additional imaging to complete the picture.
| Test | What it does |
|---|---|
| Abdominal ultrasound | First-line test; detects gallstones with high accuracy |
| HIDA scan (cholescintigraphy) | Checks gallbladder emptying and detects a blocked cystic duct |
| MRCP | MRI-based scan that spots bile-duct stones missed by ultrasound |
| CT scan | Identifies complications such as inflammation or pancreatitis |
| ERCP | Finds and removes bile-duct stones in one procedure |
Blood tests add an important layer whenever a gallstone may be blocking bile flow, usually drawn alongside the imaging. Doctors check the total bilirubin level and the direct bilirubin level to see whether bile is backing up into the bloodstream instead of draining normally into the intestine. Reviewing the alkaline phosphatase result helps confirm this kind of blockage, called cholestasis, since the enzyme typically climbs when bile cannot flow past an obstruction. Because alkaline phosphatase can also rise from bone conditions, checking the gamma-glutamyl transferase level at the same time confirms that a rising alkaline phosphatase is coming from the liver or bile ducts rather than the bones. Blocked bile flow can irritate the liver itself, so tracking the ALT liver enzyme and the AST liver enzyme is a standard part of the picture too. Finally, a sharply elevated lipase level points toward gallstone pancreatitis, and understanding the causes and symptoms of pancreatitis explains why this combination needs urgent attention.
Treatment options for gallstones
Most people with gallstones need no treatment at all. Silent stones that cause no symptoms are typically managed with watchful waiting, since treating a stone that is not causing problems adds risk without a clear benefit. When stones do cause symptoms or complications, care moves from observation to more active options, from a single outpatient surgery to procedures aimed specifically at a stone stuck in the bile duct.
| Approach | Role |
|---|---|
| Watchful waiting | For silent, symptom-free stones; no treatment needed unless symptoms develop |
| Laparoscopic cholecystectomy | Standard outpatient surgery that removes the gallbladder for good |
| ERCP | Removes stones lodged in the common bile duct |
| Oral bile acid medication (ursodiol) or lithotripsy | Rarely used to dissolve or break up select small cholesterol stones |
Laparoscopic cholecystectomy is the standard, most effective treatment: a surgeon removes the gallbladder through a few small incisions, and most people go home the same day or after one night, with a full recovery in about one to two weeks. If a stone has moved into the common bile duct, ERCP locates and clears it, either shortly before surgery or during the same hospital stay. Oral bile acid medication and shock-wave lithotripsy are used only rarely, for people with small cholesterol stones who cannot safely have surgery, since both work slowly and stones often return once treatment stops. Because the gallbladder is not essential for digestion, removing it resolves gallstone disease for good in the vast majority of people.
Living with gallstones and long-term outlook
Life without a gallbladder is normal and safe, and most people who have it removed go on to eat a regular diet with no lasting restrictions. Without a gallbladder to store it, bile drips more continuously from the liver straight into the small intestine instead of being released in a concentrated burst after meals. Some people notice looser stools for the first few weeks, especially after a large or fatty meal, but this usually settles as the body adjusts.
For people with silent gallstones who choose watchful waiting, the outlook is also reassuring: most silent stones never cause symptoms, and no diet or medication reliably prevents or dissolves them. Still, it helps to know the warning signs of a complication, such as pain lasting several hours, fever, or jaundice, so care is not delayed if a silent stone becomes active. Maintaining a healthy weight through gradual change rather than rapid weight loss, eating regular meals, and getting enough fiber can help support gallbladder health long term. With appropriate treatment when needed, gallstones are rarely a long-term threat to health.
Latest scientific advances in gallstone research
Research continues to refine when surgery is worth it and how it is best performed. According to PubMed-indexed research, a 2026 meta-analysis of 4 randomized trials in patients with uncomplicated symptomatic gallstones or mild cholecystitis found that gallbladder removal cut recurrent biliary colic by more than half and reduced overall complications compared with conservative management, though conservative management had fewer surgical complications and mortality did not differ (Gad et al., 2026). What this means for you: with mild, uncomplicated symptoms, surgery offers better long-term symptom control, but conservative management remains a reasonable, lower-risk option to discuss with your doctor rather than an automatic need for an operation. Technique also matters when the bile duct is involved: a 2026 network meta-analysis of 52 studies and more than 11,000 patients found that newer, T-tube-free approaches matched traditional T-tube drainage for safety while shortening operating time and hospital stay (Liao et al., 2026). What this means for you: if you need surgery for stones in both the gallbladder and bile duct, ask whether a T-tube-free technique is an option.
A separate line of research has focused on a modern risk factor: GLP-1 receptor agonist drugs used for diabetes and weight loss. According to PubMed-indexed research, a 2026 cohort study of more than 150,000 people with type 2 diabetes found that those taking a GLP-1 receptor agonist had meaningfully higher three-year rates of gallstones, cholecystitis, and gallbladder removal than non-users, with the clearest signal for semaglutide and dulaglutide (Eldesouki et al., 2026). What this means for you: if you are taking a GLP-1 drug such as semaglutide or tirzepatide, know that it carries a modestly increased gallstone risk, so new abdominal pain is worth mentioning to your doctor.
Glossary of key gallstone terms
| Term | Definition |
|---|---|
| Cholelithiasis | The medical term for the presence of gallstones in the gallbladder. |
| Cholesterol stone | A gallstone made mostly of hardened cholesterol; the most common type in the United States. |
| Pigment stone | A darker gallstone formed from excess bilirubin rather than cholesterol. |
| Biliary colic | Sudden pain from a gallstone temporarily blocking the flow of bile, often after a fatty meal. |
| Cholecystitis | Inflammation of the gallbladder, usually caused by a stone blocking its outlet. |
| Choledocholithiasis | A gallstone that has moved out of the gallbladder into the common bile duct. |
| Cholecystectomy | Surgery to remove the gallbladder, most often performed laparoscopically. |
Frequently asked questions about gallstones
What are the first signs of a gallbladder attack?
A gallbladder attack, or biliary colic, usually starts as sudden, intense pain in the upper right or center of the abdomen, often after a fatty meal. The pain can spread to the back or right shoulder blade, often with nausea or vomiting, and builds quickly rather than coming and going.
What causes gallstones to form?
Gallstones form when substances in bile fall out of balance. Cholesterol stones develop when bile holds more cholesterol than it can keep dissolved, while pigment stones form from excess bilirubin, often tied to liver disease. A gallbladder that does not empty completely lets these substances concentrate into stones over time.
How long does a gallbladder attack last?
A typical episode of biliary colic lasts about 30 minutes to a few hours before easing on its own. Pain lasting more than several hours, especially with fever or chills, suggests a complication such as cholecystitis and needs prompt medical attention.
How is gallbladder removal (cholecystectomy) performed, and what is recovery like?
Most gallbladder removals are done as a laparoscopic cholecystectomy, using a camera and slender instruments through a few small incisions. Most people go home the same day or after one night and return to normal activities within one to two weeks. Since the gallbladder is not needed for digestion, removing it resolves gallstone disease for good.
Can Ozempic or other GLP-1 weight-loss drugs cause gallstones?
GLP-1 receptor agonists such as semaglutide, tirzepatide, and liraglutide are linked to a higher risk of gallstones, likely from rapid weight loss and slower gallbladder emptying. Research has found meaningfully higher rates of gallstones, cholecystitis, and gallbladder removal among people taking these drugs, so new abdominal pain while on one is worth mentioning to your doctor.
What blood tests show gallstones or a blocked bile duct?
No blood test can see a gallstone directly, but several results point toward one causing a problem. Rising total and direct bilirubin, alkaline phosphatase, and gamma-glutamyl transferase suggest a blocked bile duct, while elevated ALT and AST point to liver irritation from that blockage. A sharply elevated lipase level suggests gallstone pancreatitis, a more serious complication needing urgent care.
Sources
- National Institute of Diabetes and Digestive and Kidney Diseases — Definition & Facts for Gallstones — NIDDK, 2023 — niddk.nih.gov
- Mayo Clinic — Gallstones – Symptoms and causes — Mayo Clinic, 2024 — mayoclinic.org
- Cleveland Clinic — Gallstones — Cleveland Clinic Health Library, 2023 — my.clevelandclinic.org
- Gad MM, Ayad Q, Elgamal MM, et al. — Cholecystectomy versus conservative management for patients with uncomplicated symptomatic gallstones and cholecystitis: an updated systematic review and meta-analysis — BMC Surgery, 2026 — doi.org/10.1186/s12893-026-03922-z
- Liao Z, Zhu X, Wang Y, et al. — Minimally invasive surgical strategies for gallbladder stones with concomitant common bile duct stones: a systematic review and network meta-analysis — BMC Surgery, 2026 — doi.org/10.1186/s12893-026-04003-x
- Eldesouki MH, Alkasabrah O, Kloub M, et al. — Cohort Study: Risk of Gallstones and Biliary Complications With Glucagon-Like Peptide-1 Receptor Agonists in Type 2 Diabetes — United European Gastroenterology Journal, 2026 — doi.org/10.1002/ueg2.70238
Further reading
- See how technology is changing test interpretation in this guide to a high ALT or AST result.
- Build confidence reading test results with this guide to reference ranges, flags, and next steps on a lab report.
Understand your lab results with BloodSense
Gallstones sit at the crossroads of digestion and liver health, and the same blood tests used to look for a blocked bile duct also say a great deal about how the liver and biliary system are doing overall. Bilirubin, alkaline phosphatase, gamma-glutamyl transferase, ALT, AST, and lipase each capture a different part of the picture, and seeing how they move together makes it easier to tell a passing fatty-meal twinge from a pattern your doctor should know about. BloodSense translates a full lab report into plain language, showing what each marker means and helping you track changes over time so you can bring clear questions to your next appointment.
