It causes fever, chills, nausea and vomiting, and severe pain in the upper-right quadrant of the abdomen. Heartbeat may become rapid and the patient may experience a drop in blood pressure. Most gallstones provoke no symptoms at all. Asymptomatic gallstones seldom lead to problems. Serious effects from gallstones are usually from stones in the bile duct or surgical complications.
Gallbladder cancer is very rare, however, even among people with gallstones.
People who have symptomatic gallstones, however, have four times the risk as those without symptoms. Whether gallstones themselves cause the cancer, or whether some factor in bile is responsible for both conditions is unknown. One study demonstrated that gallbladder removal reduced the likelihood of bile duct cancer, suggesting that gallstones themselves were responsible. Perforation and gangrene or abscess formation may occur when severe symptoms persist for many days. The risk for perforation increases with a condition called emphysematous cholecystitis, in which gas forms in the gallbladder.