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Gallstones are solid pieces of material that form in the gallbladder, which is the sac located on the undersurface of the liver in the upper right-hand portion of the stomach cavity. The gallbladder aids in digestion by storing bile, which is produced and secreted continuously by the liver. After a meal, the gallbladder contracts and sends the stored bile into the intestine. When digestion of the meal is over, the gallbladder relaxes and continues to store bile.

About one million new cases of gallstones are diagnosed every year in the United States, and an estimated one in 10 people suffer from the condition, which is particularly common during the mid-life years. Women tend to develop gallstones more commonly than men and at a younger age.

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Gallstones vary in size and volume, ranging from the size of a grain of sand to the size of a plum. The gallbladder may develop a single, often large stone or many smaller ones, even several thousand. Gallstones occur when the gallbladder crystallizes the components of bile it concentrates. Bile is a brown liquid containing bile salts, cholesterol, bilirubin and lecithin. Risk factors for developing gallstones include obesity, inherited body chemistry, body weight, sluggish gallbladder movement, hormones and possibly diet. For instance, very low calorie, rapid weight-loss diets and prolonged fasting, have been shown to cause gallstones. Some proteins in bile also can promote or inhibit gallstone development.

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Many people do not experience any symptoms and are said to have "silent gallstones." Often the gallstones are found when a test is performed to evaluate some other problem. Treatment is only recommended if a person actually experiences symptoms of the condition.

A severe and steady pain in the upper abdomen or right side is the most common symptom of gallstones. The pain, which also may affect the shoulder blades or right shoulder, lasts anywhere from several minutes to hours. In addition, you may experience sweating or vomiting.

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Your doctor will first ask about your medical history and perform a physical examination. In addition, he or she may order the following tests:

  • Computed Tomography (CT) Scan: An X-ray that uses a computer to provide an image of the inside of the abdomen.
  • Magnetic Resonance Imaging (MRI) Scan: This test uses magnetic waves to create an image.
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Gallstones may be treated with surgery and medications.


If surgery is required, the following procedures may be used:

  • Cholecystectomy: Surgical removal of the gallbladder, a procedure called cholecystectomy, is the most widely used therapy for gallstones, although this procedure is now mostly done laparoscopically. Though in some cases, due to infections or other surgeries, this traditional form of cholecystectomy will be performed. Four or five days of hospitalization are generally required for this procedure. Patients often do well after surgery and have no difficulty with digesting food.
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UCSF Clinics & Centers


Gastroenterology at Mount Zion
1701 Divisadero St., Suite 120
San Francisco, CA 94115
Phone: (415) 502-4444
Fax: (415) 502-2249
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Gastroenterology at Parnassus
350 Parnassus Ave., Suite 410
San Francisco, CA 94143
Phone: (415) 502-2112
Fax: (415) 514-3300
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Gastrointestinal Motility & Secretion Center
400 Parnassus Ave., Box 0310
San Francisco, CA 94143-0310
Phone: (415) 353-9383
Fax: (415) 353-2505
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