Alcohol abuse and gallstones are the two leading causes of pancreatitis. It is not fully understood how alcohol impacts the pancreas. However, scientists do know that it causes the premature release of digestive enzymes. It also impacts the small ducts that transport enzymes within the pancreas and causes digestive juices to leak into surrounding tissues and organs and damage them. Alcohol also causes the formation of protein plugs that can block parts of the pancreatic duct. An attack can occur from a few hours to several days after drinking alcohol.

Gallstones are hard, stone-like masses formed from substances in bile (e.g., cholesterol, bilirubin) that develop in the gallbladder or bile ducts. Gallstones can move from the gallbladder or bile ducts to the pancreatic duct and block the flow of digestive enzymes into the duodenum (upper part of the small intestine). As a result, the enzymes become active in the pancreas and cause damage.

Though alcohol and gallstones have been identified as causes of pancreatitis, scientists believe environmental and genetic factors may also play a role in development of the disease. Factors that may contribute to pancreatitis include:

• Increased level of substances in the blood. These may include triglycerides (fats) in the blood (hyperlipidemia) or calcium in the blood (hypercalcemia).
  
  
• Medications. Certain types of medications may contribute to pancreatitis, such as nonsteroidal anti-inflammatory drugs (NSAIDs) and antibiotics. Common prescription medications like some loop diuretics (to reduce water in the body), HIV medications and chemotherapy drugs are also known to incite inflammation of the pancreas.
  
  
• Damage to the pancreas. This may result from abdominal surgery, trauma or other causes.
  
  
• Structural abnormalities. These may occur in the pancreas or bile duct.
  
  
• Infections. These can include hepatitis, Epstein-Barr virus and bacterial infections. The condition may also result from mumps, though this is rare.
  
  
• Heredity. This can include inherited conditions, such as cystic fibrosis.
  
  
• Endoscopic retrograde cholangiopancreatography (ERCP). A test that involves injecting a dye into the bile and pancreatic ducts. Acute pancreatitis develops in a small number of patients who undergo this procedure.
  
  
• Pancreatic cancer.
  
  
• Scorpion stings. People who have been stung by certain species of scorpions may develop pancreatitis.

In approximately 15 percent of cases, the cause of pancreatitis is unknown (idiopathic).

There are many factors that increase the risk of developing pancreatitis. Although long-term alcohol abuse is the primary risk factor for pancreatitis, only a small percentage of people with alcoholism develop pancreatitis. For this reason, scientists believe there are other factors that contribute to its development. They include:

• Gallbladder disease. This can result in the formation of gallstones, which are one of the primary causes of pancreatitis.
  
  
• Gender. More men than women develop pancreatitis. This may be because men are more likely to abuse alcohol.
  
  
• Ethnicity. Pancreatitis is more prevalent among black Americans than white Americans.
  
  
• Heredity. Abnormalities in genes and some inherited conditions, such as cystic fibrosis, may place a patient at a higher risk of developing pancreatitis.
  
  
• Exposure to toxins. The stress to the body from metabolizing cigarette smoke or pollution may strain the pancreas and contribute to pancreatitis.