Pain is the most common presenting symptom. It is usually described as sharp right upper quadrant pain that radiates to the right shoulder, or less commonly, behind the breastbone. Nausea and vomiting can be associated with biliary colic. Individuals may also present with pain that is induced following a fatty meal and the symptom of indigestion. The pain often lasts longer than 30 minutes, up to a few hours.

Patients usually have normal vital signs with biliary colic, whereas patients with cholecystitis are usually febrile and more ill appearing. Lab studies that should be ordered include a complete blood count, liver function tests and lipase. In biliary colic, lab findings are usually within normal limits. Alanine aminotransferase and aspartate transaminase are usually suggestive of liver disease whereas elevation of bilirubin and alkaline phosphatase suggests common bile duct obstruction. Pancreatitis should be considered if the lipase value is elevated; gallstone disease is the major cause of pancreatitis.

Biliary colic, also known as a gallbladder attack or gallstone attack, is when pain occurs due to a gallstone temporarily blocking the bile duct. Typically, the pain is in the right upper part of the abdomen, and it can radiate to the shoulder. Pain usually lasts from one to a few hours. Often, it occurs after eating a heavy meal, or during the night. Repeated attacks are common.

Gallstone formation occurs from the precipitation of crystals that aggregate to form stones. The most common form is cholesterol gallstones. Other forms include calcium, bilirubin, pigment, and mixed gallstones. Other conditions that produce similar symptoms include appendicitis, stomach ulcers, pancreatitis, and gastroesophageal reflux disease.

Treatment for gallbladder attacks is typically surgery to remove the gallbladder. This can be either done through small incisions or through a single larger incision. Open surgery through a larger incision is associated with more complications than surgery through small incisions. Surgery is typically done under general anesthesia. In those who are unable to have surgery, medication to try to dissolve the stones or shock wave lithotripsy may be tried. , it is not clear whether surgery is indicated for everyone with biliary colic.

In the developed world, 10-15% of adults have gallstones. Of those with gallstones, biliary colic occurs in 1–4% each year. Nearly 30% of people have further problems related to gallstones in the year following an attack. About 15% of people with biliary colic eventually develop inflammation of the gallbladder if not treated. Other complications include inflammation of the pancreas.

Under a microscope, the individual hepatocytes will have a brownish-green stippled appearance within the cytoplasm, representing bile that cannot get out of the cell. Canalicular bile plugs between individual hepatocytes or within bile ducts may also be seen, representing bile that has been excreted from the hepatocytes but cannot go any further due to the obstruction. When these plugs occur within the bile duct, sufficient pressure (caused by bile accumulation) can cause them to rupture, spilling bile into the surrounding tissue, causing hepatic necrosis. These areas are known as bile lakes, and are typically seen only with extra-hepatic obstruction.

Cholestasis is a condition where bile cannot flow from the liver to the duodenum. The two basic distinctions are an obstructive type of cholestasis where there is a mechanical blockage in the duct system that can occur from a gallstone or malignancy, and metabolic types of cholestasis which are disturbances in bile formation that can occur because of genetic defects or acquired as a side effect of many medications.

Functional disorders of the gallbladder, bile duct and pancreas have been defined and classified by the Rome criteria for functional gastrointestinal disorders. The criteria outline three variants of functional disorders of the gallbladder, bile duct and pancreas, termed "functional gallbladder disorder", "functional biliary sphincter of Oddi disorder" and "functional pancreatic sphincter of Oddi disorder". All of the following criteria need to be met for as part of the definition of a functional disorder of the gallbladder:

- the pain must be located in the upper part of the abdomen and/or the right upper quadrant of the abdomen

- episodes of pain must last at least 30 minutes

- the symptoms must be recurrent, and occur at differing intervals

- the pain must incrementally increase to a "steady level"

- the pain must be severe enough the patient's daily activities are affected, or that the patient must attend the emergency department

- the pain must not be relieved by any of bowel movements, change in posture, or antacids; and,

- other structural disorders that could explain the symptoms must be excluded.

Individuals are classified as having a functional gallbladder disorder if the above criteria are met, if the gallbladder is present, and if the testing of liver enzymes, conjugated bilirubin, and pancreatic enzymes (amylase and lipase) are normal.

They form as a result of increased pressure in the gallbladder and recurrent damage to the wall of the gallbladder.

Rokitansky–Aschoff sinuses, also entrapped epithelial crypts, are pseudodiverticula or pockets in the wall of the gallbladder. They may be microscopic or macroscopic.

Histologically, they are outpouchings of gallbladder mucosa into the gallbladder muscle layer and subserosal tissue as a result of hyperplasia and herniation of epithelial cells through the fibromuscular layer of the gallbladder wall. They are usually referred to as adenomyomatosis.

They are not of themselves considered abnormal, but they can be associated with cholecystitis.

Early symptoms mimic gallbladder inflammation due to gallstones. Later, the symptoms may be that of biliary and stomach obstruction.

Of note, Courvoisier's law states that in the presence of a palpably enlarged gallbladder which is nontender and accompanied with mild painless jaundice, the cause is unlikely to be gallstones. This implicates possible malignancy of the gallbladder or pancreas, and the swelling is unlikely due to gallstones due to the chronic inflammation association with gallstones leading to a shunken, non-distensible gallbladder. However, Ludwig Georg Courvoisier's original observations, published in Germany in 1890, were not originally cited as a 'law', and no mention of malignancy or pain (tenderness) was made. These points are commonly missquoted or confused in the medical literature.

Biliary injury (bile duct injury) is the traumatic damage of the bile ducts. It is most commonly an iatrogenic complication of cholecystectomy — surgical removal of gall bladder, but can also be caused by other operations or by major trauma. The risk of biliary injury is more during laparoscopic cholecystectomy than during open cholecystectomy. Biliary injury may lead to several complications and may even cause death if not diagnosed in time and managed properly. Ideally biliary injury should be managed at a center with facilities and expertise in endoscopy, radiology and surgery.

Duodenal cancer is a cancer in the beginning section of the small intestine. It is relatively rare compared to gastric cancer and colorectal cancer. Its histology is usually adenocarcinoma.

Familial adenomatous polyposis (FAP), Gardner syndrome, Lynch syndrome, Muir–Torre syndrome, celiac disease, Peutz–Jeghers syndrome, Crohn's disease and juvenile polyposis syndrome are risk factors for developing this cancer.

The duodenum is the first part of the small intestine. It is located between the stomach and the jejunum. After foods combine with stomach acid, they descend into the duodenum where they mix with bile from the gallbladder and digestive juices from the pancreas.

A vesicointestinal fistula (or intestinovesical fistula) is a form of fistula between the bladder and the bowel.

In humans, enteroliths are rare and may be difficult to distinguish from gall stones. Their chemical composition is diverse, and rarely can a nidus be found. A differential diagnosis of an enterolith requires the enterolith, a normal gallbladder, and a diverticulum.

An enterolith typically forms within a diverticulum. An enterolith formed in a Meckel's diverticulum sometimes is known as a Meckel's enterolith. Improper use of magnesium oxide as a "long-term" laxative has been reported to cause enteroliths and/or medication bezoars.

Most enteroliths are not apparent and cause no complications. However, any complications that do occur are likely to be severe. Of these, bowel obstruction is most common, followed by ileus and perforation. Bowel obstruction and ileus typically occur when a large enterolith is expelled from a diverticulum into the lumen. Perforation typically occurs within the diverticulum.

Most human enteroliths are radiolucent on plain X-rays. They sometimes can be visualized on CT scans without contrast; presence of contrast in the lumen may reveal the enterolith as a void. Most often, they are visualized using ultrasound.

Although recent surveys of enterolith composition are lacking, one early review notes struvite (as in equines), calcium phosphate, and calcium carbonate and reports choleic acid. Deoxycholic acid and cholic acid have also been reported.

A fistula involving the bladder can have one of many specific names, describing the specific location of its outlet:

- Bladder and intestine: "vesicoenteric", "enterovesical", or "vesicointestinal"

- Bladder and colon: "vesicocolic" or "colovesical"

- Bladder and rectum: "vesicorectal" or "rectovesical"

An enterolith is a mineral concretion or calculus formed anywhere in the gastrointestinal system. Enteroliths are uncommon and usually incidental findings but, once found, they require at a minimum watchful waiting. If there is evidence of complications, they must be removed.

An enterolith may form around a "nidus", a small foreign object such as a seed, pebble, or piece of twine, that serves as an irritant. In this respect, an enterolith forms by a process similar to the creation of a pearl.

An enterolith is not to be confused with a gastrolith, which helps digestion.

Xanthogranulomatous cholecystitis (XGC) is a rare form of gallbladder disease which mimics gallbladder cancer although it is not cancerous. It was first discovered and reported in the medical literature in 1976 by J.J. McCoy, Jr., and colleagues.

The cancerous mass tends to block food from getting to the small intestine. If food cannot get to the intestines, it will cause pain, acid reflux, and weight loss because the food cannot get to where it is supposed to be processed and absorbed by the body.

Patients with duodenal cancer may experience abdominal pain, weight loss, nausea, vomiting, and chronic GI bleeding.

Colic (from Greek κολικός "kolikos", "relative to the colon") or cholic is a form of pain that starts and stops abruptly. It occurs due to muscular contractions of a hollow tube (colon, ureter, gall bladder, etc.) in an attempt to relieve an obstruction by forcing content out. It may be accompanied by vomiting and sweating. Types include:

- Baby colic, a condition, usually in infants, characterized by incessant crying

- Renal colic, a pain in the flank, characteristic of kidney stones

- Biliary colic, blockage by a gallstone of the common bile duct or cystic duct

- Horse colic, a potentially fatal condition experienced by horses, caused by intestinal displacement or blockage

- Devon colic, an affliction caused by lead poisoning

- Painter's colic or lead poisoning

Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract (GI tract) and accessory organs of digestion, including the esophagus, stomach, biliary system, pancreas, small intestine, large intestine, rectum and anus. The symptoms relate to the organ affected and can include obstruction (leading to difficulty swallowing or defecating), abnormal bleeding or other associated problems. The diagnosis often requires endoscopy, followed by biopsy of suspicious tissue. The treatment depends on the location of the tumor, as well as the type of cancer cell and whether it has invaded other tissues or spread elsewhere. These factors also determine the prognosis.

Overall, the GI tract and the accessory organs of digestion (pancreas, liver, gall bladder) are responsible for more cancers and more deaths from cancer than any other system in the body. There is significant geographic variation in the rates of different gastrointestinal cancers.

Calculi are usually asymptomatic, and large calculi may have required many years to grow to their large size.

A calculus (plural calculi), often called a stone, is a concretion of material, usually mineral salts, that forms in an organ or duct of the body. Formation of calculi is known as lithiasis (). Stones can cause a number of medical conditions.

Some common principles (below) apply to stones at any location, but for specifics see the particular stone type in question.

Calculi are not to be confused with gastroliths.

Urethral diverticula are often asymptomatic and symptoms that are present tend to be nonspecific. They can co-occur with cancer, in approximately 6-9% of cases, most commonly adenocarcinoma, but also including squamous cell carcinoma and transitional cell carcinoma. Approximately 10% of cases co-occur with kidney stones.

There are 2 types of urethral diverticulums. Congenital and acquired. In infancy usually the urethral diverticulum is congenital but in rare instances acquired urethral diverticulum can be seen in infancy specially following traumatic catheterization.

Common symptoms of urethral diverticulum include incontinence, urinary frequency and urgency, pain during sex, and pain during urination. Other symptoms include pain localized to the urethra or pelvis and frequent urinary tract infection.

When urethral diverticulum becomes severe, a painful mass can sometimes be felt inside the introitus of the vagina, which can discharge pus. If the mass is hard or bleeds, complications like cancer or kidney stones may be present.

Hunner's Ulcers occur in 5 to 10 percent of people who have the bladder disease Interstitial cystitis. They form on the wall of the bladder and, like any ulcer, they can bleed, ooze, and may vary in size. They were first described by Dr. Guy LeRoy Hunner, 1868–1957, a Johns Hopkins gynecologist, in a paper delivered to the Boston Medical Society in 1915.

Hunner's Ulcers can only be accurately diagnosed via a cystoscopy with hydrodistention. The procedure is performed by a urologist either as an in office procedure or while the patient is under general anaesthesia as a day surgery.

Esophageal cancer is the sixth-most-common cancer in the world, and its incidence is increasing. Some three to five males are affected for each female. An "esophageal cancer belt", in which the incidence of esophageal squamous cell carcinoma (SCC) is more than a hundred times that of adjacent areas, extends from northeastern China through central Asia to northern Iran. Ethiopia also has a notably high incidence. There are two main types of esophageal cancer—adenocarcinoma and squamous cell carcinoma. Worldwide, the incidence of each type is about the same, but in developed countries like North America and Europe adenocarcinoma is the more common.

Cancer of the esophagus is often detected late inasmuch as there are typically no early symptoms. Nevertheless, if the cancer is caught soon enough, patients can have a five-year survival rate of 90% or above. By the time esophageal cancer is usually detected, though, it might have spread beyond the esophageal wall, and the survival rate drops significantly. In China, the overall five-year survival rate for advanced esophageal cancer is about 20%, and in the United States it is about 15%.