There are two types of gallstones:

• Cholesterol Stones: About 80% of gallstones are made primarily from cholesterol. Usually white, yellow or green in color, they are formed when the gallbladder is unable to process an excess of cholesterol accumulating in the gallbladder bile.
• Pigment Stones: Pigment stones are smaller and darker than cholesterol stones, and usually occur in patients with cirrhosis or blood disorders such as thalassemia and G6PD deficiency.

• Genetics: People with a family history of gallstones are at increased risk. 
• Obesity: Obesity is a high risk factor because it increases the cholesterol in the bile.
• Estrogen and pregnancy: Estrogen and pregnancy increase cholesterol levels and decrease the motility of the gallbladder. Birth control pills and hormone replacement therapy increase the risk of developing gallstones.
• Gender and age: Gallstones are more common in women and older people.
• Diabetes: Higher triglycerides levels and decreased gallbladder movement in people with diabetes are also risk factors.
• Rapid weight loss: If a person loses weight too quickly, the liver will secrete extra cholesterol and the gallbladder does not contract often enough to empty out the bile, leading to gallstones.
• Diet: Eating a high-cholesterol and low-fiber diet increases the risk of gallstones.

Gallstones generally do not cause any symptoms. A person usually learns he or she has gallstones while being examined for another illness or during a health check-up. When symptoms do appear, they may include:

• Severe pain in the upper abdomen or right portion of the abdomen. The pain may last for 15 minutes or several hours and may radiate into the scapula or right shoulder.
• Vomiting
• Nausea
• Other gastrointestinal problems, including abdominal bloating, indigestion, heartburn, gas, and pain after eating fatty foods. 
• Acute inflammation of the gallbladder causes fever, pain in the right hypochondriac region, yellowing of the skin and eyes, and darkened urine.

• Evaluation of patient history and a physical examination
• Blood test to check the functioning of the liver 
• Abdominal ultrasound

• Gallbladder surgery
  • Open cholecystectomy
  • Laparoscopic cholecystectomy
• Endoscopic retrograde cholangiopancreatography (ERCP) is performed if the stones are in the bile ducts.

The gallbladder is an organ where bile is stored. Once the gallbladder is removed, bile flows directly from the liver, where it is made, through the small intestine. The bile is less concentrated, but it has no effect on digestion. Approximately 10% of people without a gallbladder may experience diarrhea from the excessive flow of bile.
 
Laparoscopic cholecystectomy should only be performed by a specialist because of the risk of complications, such as unintended injury to the common bile duct, bile leakage, or bile duct blockage.